From 5e704f02f666ce3155213f95a097c64feecd2ec5 Mon Sep 17 00:00:00 2001
From: Emerick Rogul <erogul@brave.com>
Date: Mon, 6 Jan 2025 15:55:07 -0500
Subject: [PATCH] Remove ts-nocheck from brave://settings files

---
 ...ave_clear_browsing_data_dialog_behavior.ts | 127 +++++----
 .../brave_clear_browsing_data_on_exit_page.ts | 144 ++++++----
 .../settings/brave_overrides/about_page.ts    |  22 +-
 .../settings/brave_overrides/basic_page.ts    |   6 +-
 .../clear_browsing_data_dialog.ts             |  14 +-
 .../brave_overrides/default_browser_page.ts   |  18 +-
 .../brave_overrides/import_data_dialog.ts     |  10 +-
 .../brave_overrides/page_visibility.ts        |  20 +-
 .../settings/brave_overrides/settings_menu.ts |  55 ++--
 .../settings/brave_overrides/settings_ui.ts   |  43 +--
 .../settings/brave_overrides/site_details.ts  |  87 +++---
 .../brave_overrides/site_settings_page.ts     |  75 +++--
 .../brave_reset_profile_dialog_behavior.ts    |  11 +-
 browser/resources/settings/brave_routes.ts    |  12 +-
 .../brave_sync_page/brave_sync_subpage.ts     | 253 ++++++++---------
 .../brave_tor_bridges_dialog.ts               |  61 ++--
 .../brave_tor_page/brave_tor_browser_proxy.ts |  12 +-
 ...ave_tor_snowflake_install_failed_dialog.ts |  15 +-
 .../brave_tor_page/brave_tor_subpage.ts       | 187 +++++++-----
 .../brave_wallet_browser_proxy.ts             |   6 +-
 .../brave_wallet_page/brave_wallet_page.ts    | 267 +++++++++++-------
 .../brave_wallet_page/wallet_networks_list.ts | 197 ++++++++-----
 .../wallet_networks_subpage.ts                |  49 ++--
 .../brave_adblock_browser_proxy.ts            | 138 +++++----
 .../brave_adblock_subpage.ts                  | 115 +++++---
 .../components/brave_adblock_editor.ts        |  22 +-
 .../brave_adblock_subscribe_dropdown.ts       |  36 +--
 .../default_brave_shields_browser_proxy.ts    | 138 +++------
 .../default_brave_shields_page.ts             |  71 +++--
 .../pin_shortcut_page/pin_shortcut_page.ts    |  25 +-
 .../brave_overrides/certificate_manager_v2.ts |   2 -
 31 files changed, 1253 insertions(+), 985 deletions(-)

diff --git a/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.ts b/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.ts
index 3508c4278592..e8389f1970fe 100644
--- a/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.ts
+++ b/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.ts
@@ -1,39 +1,48 @@
-// @ts-nocheck
 /* Copyright (c) 2019 The Brave Authors. All rights reserved.
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * you can obtain one at https://mozilla.org/MPL/2.0/. */
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+import './brave_clear_browsing_data_on_exit_page.js'
 
-import "./brave_clear_browsing_data_on_exit_page.js"
+import {CrButtonElement} from 'chrome://resources/cr_elements/cr_button/cr_button.js'
+import {
+  SettingsBraveClearBrowsingDataOnExitPageElement
+} from './brave_clear_browsing_data_on_exit_page.js'
 
-import {loadTimeData} from "../i18n_setup.js"
-import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js';
-import {SettingsClearBrowsingDataDialogElement} from '../clear_browsing_data_dialog/clear_browsing_data_dialog.js'
-import type {SettingsClearBrowsingDataDialogElement as BraveSettingsClearBrowsingDataDialogElement}
-    from '../clear_browsing_data_dialog/clear_browsing_data_dialog.js'
-import {BraveClearBrowsingDataDialogBrowserProxy, BraveClearBrowsingDataDialogBrowserProxyImpl}
-    from './brave_clear_browsing_data_dialog_proxy.js'
+import {loadTimeData} from '../i18n_setup.js'
 
-const BaseElement = WebUiListenerMixin(SettingsClearBrowsingDataDialogElement)
-export class BraveSettingsClearBrowsingDataDialogElement extends BaseElement {
-  braveRewardsEnabled_: Boolean = false;
-  onClearBraveAdsDataClickHandler_: (() => void) = () => {};
+import {
+  SettingsClearBrowsingDataDialogElement
+} from '../clear_browsing_data_dialog/clear_browsing_data_dialog.js'
 
-  private clearDataBrowserProxy_ =
-      BraveClearBrowsingDataDialogBrowserProxyImpl.getInstance();
-  private onSelectedPageChangedCallback_: (() => void) | null = null;
-  private updateSaveButtonStateCallback_: (() => void) | null = null;
-  private saveOnExitSettingsCallback_: (() => void) | null = null;
+import {
+  BraveClearBrowsingDataDialogBrowserProxy,
+  BraveClearBrowsingDataDialogBrowserProxyImpl
+} from './brave_clear_browsing_data_dialog_proxy.js'
+
+export class BraveSettingsClearBrowsingDataDialogElement
+extends SettingsClearBrowsingDataDialogElement {
+  braveRewardsEnabled_: Boolean = false
+  onClearBraveAdsDataClickHandler_: ((e: Event) => void) = () => {}
+
+  private clearDataBrowserProxy_: BraveClearBrowsingDataDialogBrowserProxy =
+    BraveClearBrowsingDataDialogBrowserProxyImpl.getInstance()
+
+  private onSelectedPageChangedCallback_: (() => void) | null = null
+
+  private updateSaveButtonStateCallback_: (() => void) | null = null
+
+  private saveOnExitSettingsCallback_: (() => void) | null = null
 
   override ready() {
-    super.ready();
+    super.ready()
 
     // Append On exit tab to tab selector.
-    this.tabsNames_.push(loadTimeData.getString('onExitPageTitle'));
+    ;(this as any).tabsNames_.push(loadTimeData.getString('onExitPageTitle'))
 
     this.addWebUiListener(
-      'update-counter-text', this.updateOnExitCountersText.bind(this))
+      'update-counter-text', this.updateOnExitCountersText_.bind(this))
 
     this.addWebUiListener(
       'brave-rewards-enabled-changed', (enabled: boolean) => {
@@ -56,9 +65,9 @@ export class BraveSettingsClearBrowsingDataDialogElement extends BaseElement {
     this.shadowRoot!.querySelector('#on-exit-tab')!.addEventListener(
       'clear-data-on-exit-page-change', this.updateSaveButtonStateCallback_)
 
-    this.saveOnExitSettingsCallback_ = this.saveOnExitSettings_.bind(this);
-    this.shadowRoot.querySelector('#saveOnExitSettingsConfirm').addEventListener(
-      'click', this.saveOnExitSettingsCallback_);
+    this.saveOnExitSettingsCallback_ = this.saveOnExitSettings_.bind(this)
+    this.shadowRoot!.querySelector('#saveOnExitSettingsConfirm')!
+      .addEventListener('click', this.saveOnExitSettingsCallback_)
 
     this.onClearBraveAdsDataClickHandler_ = this.clearBraveAdsData_.bind(this)
   }
@@ -72,16 +81,17 @@ export class BraveSettingsClearBrowsingDataDialogElement extends BaseElement {
       this.onSelectedPageChangedCallback_ = null
     }
 
-    if (this.saveOnExitSettingsCallback_) {
-      this.shadowRoot.querySelector('#on-exit-tab').removeEventListener(
-        'clear-data-on-exit-page-change', this.updateSaveButtonStateCallback_);
-      this.updateSaveButtonStateCallback_ = null;
+    if (this.updateSaveButtonStateCallback_) {
+      this.shadowRoot!.querySelector('#on-exit-tab')!.removeEventListener(
+        'clear-data-on-exit-page-change', this.updateSaveButtonStateCallback_)
+      this.updateSaveButtonStateCallback_ = null
     }
 
     if (this.saveOnExitSettingsCallback_) {
-      this.shadowRoot.querySelector('#saveOnExitSettingsConfirm').removeEventListener(
-        'click', this.saveOnExitSettingsCallback_);
-      this.saveOnExitSettingsCallback_ = null;
+      this.shadowRoot!.
+        querySelector('#saveOnExitSettingsConfirm')!.
+        removeEventListener('click', this.saveOnExitSettingsCallback_)
+      this.saveOnExitSettingsCallback_ = null
     }
 
     this.onClearBraveAdsDataClickHandler_ = () => {}
@@ -92,60 +102,67 @@ export class BraveSettingsClearBrowsingDataDialogElement extends BaseElement {
   * preference.
   * @param {string} prefName Browsing data type deletion preference.
   * @param {string} text The text with which to update the counter
-  * @private
   */
-  updateOnExitCountersText(prefName, text) {
+  private updateOnExitCountersText_(prefName: string, text: string) {
     // Data type deletion preferences are named "browser.clear_data.<datatype>".
     // Strip the common prefix, i.e. use only "<datatype>".
-    const matches = prefName.match(/^browser\.clear_data\.(\w+)$/);
-    this.shadowRoot.querySelector('#on-exit-tab').setCounter(matches[1], text);
+    const matches = prefName.match(/^browser\.clear_data\.(\w+)$/)
+    if (matches) {
+      this.shadowRoot!.
+        querySelector<SettingsBraveClearBrowsingDataOnExitPageElement>(
+          '#on-exit-tab')!.setCounter(matches[1], text)
+    }
   }
 
   /**
    * Updates Clear and Save buttons visibility based on the selected tab.
-   * @private
    */
-  onSelectedPageChanged_() {
-    const page = this.$.pages.selectedItem;
+  private onSelectedPageChanged_() {
+    const page = this.$.pages.selectedItem
     if (!page) {
       return
     }
-    const isOnExitPage = (page.id === 'on-exit-tab');
-    this.$.clearButton.hidden = isOnExitPage;
-    this.shadowRoot.querySelector('#saveOnExitSettingsConfirm').hidden = !isOnExitPage;
+    const isOnExitPage = page.id === 'on-exit-tab'
+    this.$.clearButton.hidden = isOnExitPage
+    this.shadowRoot!.querySelector<CrButtonElement>(
+      '#saveOnExitSettingsConfirm')!.hidden = !isOnExitPage
   }
 
   /**
    * Updates Save button enabled state based on on-exit-tab's changed state.
-   * @private
    */
-  updateSaveButtonState_() {
-    this.shadowRoot.querySelector('#saveOnExitSettingsConfirm').disabled =
-        !this.shadowRoot.querySelector('#on-exit-tab').isModified;
+  private updateSaveButtonState_() {
+    const saveButton = this.shadowRoot!.
+      querySelector<CrButtonElement>('#saveOnExitSettingsConfirm')
+    if (saveButton) {
+      saveButton.disabled = !this.shadowRoot!.
+        querySelector<SettingsBraveClearBrowsingDataOnExitPageElement>(
+          '#on-exit-tab')!.isModified_
+    }
   }
 
   /**
    * Saves on exit settings selections.
-   * @private
    */
-  saveOnExitSettings_() {
-    const changed = this.shadowRoot.querySelector('#on-exit-tab').getChangedSettings();
+  private saveOnExitSettings_() {
+    const changed = this.shadowRoot!.
+      querySelector<SettingsBraveClearBrowsingDataOnExitPageElement>(
+        '#on-exit-tab')!.getChangedSettings()
     changed.forEach((change) => {
       this.set('prefs.' + change.key + '.value', change.value)
     })
     this.updateSaveButtonState_()
-    if (!this.clearingInProgress_) {
+    if (!(this as any).clearingInProgress_) {
       this.$.clearBrowsingDataDialog.close()
     }
   }
 
   /**
    * Clears Brave Ads data.
-   * @private
    */
-  clearBraveAdsData_(e: any) {
-    e.preventDefault();
-    this.clearDataBrowserProxy_.clearBraveAdsData();
-    this.$.clearBrowsingDataDialog.close();
+  private clearBraveAdsData_(e: Event) {
+    e.preventDefault()
+    this.clearDataBrowserProxy_.clearBraveAdsData()
+    this.$.clearBrowsingDataDialog.close()
   }
 }
diff --git a/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_on_exit_page.ts b/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_on_exit_page.ts
index 586007df111e..ab237ecd4b96 100644
--- a/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_on_exit_page.ts
+++ b/browser/resources/settings/brave_clear_browsing_data_dialog/brave_clear_browsing_data_on_exit_page.ts
@@ -3,85 +3,115 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck
-
-import {Polymer} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-import {loadTimeData} from '../i18n_setup.js';
-import '../settings_shared.css.js';
-import '../settings_vars.css.js';
-import '../controls/settings_checkbox.js';
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {BaseMixin} from '../base_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
+import {loadTimeData} from '../i18n_setup.js'
+import '../settings_shared.css.js'
+import '../settings_vars.css.js'
+import '../controls/settings_checkbox.js'
 import {getTemplate} from './brave_clear_browsing_data_on_exit_page.html.js'
 
-Polymer({
-  is: 'settings-brave-clear-browsing-data-on-exit-page',
+export interface SettingsBraveClearBrowsingDataOnExitPageElement {
+  $: {
+    checkboxes: HTMLElement,
+  }
+}
 
-  _template: getTemplate(),
+const SettingsBraveClearBrowsingDataOnExitPageElementBase =
+  PrefsMixin(BaseMixin(PolymerElement))
 
-  properties: {
-    prefs: {
-      type: Object,
-      notify: true,
-    },
+export class SettingsBraveClearBrowsingDataOnExitPageElement
+extends SettingsBraveClearBrowsingDataOnExitPageElementBase {
+  static get is() {
+    return 'settings-brave-clear-browsing-data-on-exit-page'
+  }
 
-    counters: {
-      type: Object,
-      // Will be filled as results are reported.
-      value: function() {
-        return {};
-      }
-    },
+  static get template() {
+    return getTemplate()
+  }
 
-    isModified: {
-      type: Boolean,
-      value: false,
-    },
+  static getProperties() {
+    return {
+      prefs: {
+        type: Object,
+        notify: true,
+      },
+
+      counters: {
+        type: Object,
+        // Will be filled as results are reported.
+        value() {
+          return {}
+        }
+      },
 
-    isChildAccount_: {
-      type: Boolean,
-      value: function() {
-        return loadTimeData.getBoolean('isChildAccount');
+      isModified_: {
+        type: Boolean,
+        value: false,
       },
-    },
 
-    isAIChatAndHistoryAllowed_: {
-      type: Boolean,
-      value: function() {
-        return loadTimeData.getBoolean('isLeoAssistantAllowed')
-          && loadTimeData.getBoolean('isLeoAssistantHistoryAllowed');
+      isChildAccount_: {
+        type: Boolean,
+        value() {
+          return loadTimeData.getBoolean('isChildAccount')
+        },
       },
+
+      isAIChatAndHistoryAllowed_: {
+        type: Boolean,
+        value() {
+          return loadTimeData.getBoolean('isLeoAssistantAllowed')
+              && loadTimeData.getBoolean('isLeoAssistantHistoryAllowed')
+        },
+      }
     }
-  },
+  }
+
+  public isModified_: boolean
+
+  private counters: {[k: string]: string} = {}
+  private isChildAccount_: boolean
+  private isAIChatAndHistoryAllowed_: boolean
 
-  listeners: {'settings-boolean-control-change': 'updateModified_'},
+  override ready() {
+    super.ready()
+    this.addEventListener(
+      'settings-boolean-control-change', this.updateModified_)
+  }
 
-  setCounter: function (counter: string, text: string) {
-    this.set('counters.' + counter, text);
-  },
+  public setCounter(counter: string, text: string) {
+    this.set('counters.' + counter, text)
+  }
 
-  getChangedSettings: function () {
-    let changed: {key: string, value: boolean}[] = [];
-    const boxes = this.$.checkboxes.querySelectorAll('settings-checkbox');
+  public getChangedSettings() {
+    let changed: Array<{key: string, value: boolean}> = []
+    const boxes = this.$.checkboxes.querySelectorAll('settings-checkbox')
     boxes.forEach((checkbox) => {
-      if (checkbox.checked != this.get(checkbox.pref.key, this.prefs).value) {
-        changed.push({key:checkbox.pref.key, value:checkbox.checked});
+      if (checkbox.checked !== this.get(checkbox.pref!.key, this.prefs).value) {
+        changed.push({key:checkbox.pref!.key, value:checkbox.checked})
       }
     })
     return changed
   }
 
-  updateModified_: function () {
-    let modified = false;
-    const boxes = this.$.checkboxes.querySelectorAll('settings-checkbox');
+  private updateModified_() {
+    let modified = false
+    const boxes = this.$.checkboxes.querySelectorAll('settings-checkbox')
     for (let checkbox of boxes) {
-      if (checkbox.checked != this.get(checkbox.pref.key, this.prefs).value) {
-        modified = true;
-        break;
+      if (checkbox.checked !== this.get(checkbox.pref!.key, this.prefs).value) {
+        modified = true
+        break
       }
     }
 
-    if (this.isModified !== modified) {
-      this.isModified = modified;
-      this.fire('clear-data-on-exit-page-change');
+    if (this.isModified_ !== modified) {
+      this.isModified_ = modified
+      this.fire('clear-data-on-exit-page-change')
     }
-  },
-});
+  }
+}
+
+customElements.define(
+  SettingsBraveClearBrowsingDataOnExitPageElement.is,
+  SettingsBraveClearBrowsingDataOnExitPageElement)
diff --git a/browser/resources/settings/brave_overrides/about_page.ts b/browser/resources/settings/brave_overrides/about_page.ts
index 20cd5f0bc9f4..19fd5f28fc72 100644
--- a/browser/resources/settings/brave_overrides/about_page.ts
+++ b/browser/resources/settings/brave_overrides/about_page.ts
@@ -3,9 +3,12 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import {html} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {html, RegisterPolymerTemplateModifications, RegisterStyleOverride} from 'chrome://resources/brave/polymer_overriding.js'
+import {
+  RegisterPolymerTemplateModifications,
+  RegisterStyleOverride
+} from 'chrome://resources/brave/polymer_overriding.js'
 
 import {getSectionElement} from './basic_page.js'
 
@@ -24,27 +27,34 @@ RegisterStyleOverride(
 RegisterPolymerTemplateModifications({
   'settings-about-page': (templateContent) => {
     const section = getSectionElement(templateContent, 'about')
+    if (!section) {
+      console.error('[Settings] Could not find about section')
+      return
+    }
     if (!section.querySelector('a#release-notes')) {
       const version = section.querySelector('#updateStatusMessage ~ .secondary')
       if (!version) {
-        console.error('[Brave Settings Overrides] Could not find version div')
+        console.error('[Settings] Could not find version div')
+        return
       }
 
       // Remove the class from the version, so we take the link styling.
       version.removeAttribute('class')
 
-      const parent = version.parentNode
       const wrapper = document.createElement('a')
       wrapper.setAttribute('id', 'release-notes')
       wrapper.setAttribute('target', '_blank')
       wrapper.setAttribute('rel', 'noopener noreferrer')
       wrapper.setAttribute('href', 'https://brave.com/latest/')
-      parent.replaceChild(wrapper, version)
+
+      const parent = version.parentNode
+      parent?.replaceChild(wrapper, version)
       wrapper.appendChild(version)
     }
 
     // Help link shown if update fails
-    const updateStatusMessageLink = section.querySelector('#updateStatusMessage a')
+    const updateStatusMessageLink =
+      section.querySelector<HTMLAnchorElement>('#updateStatusMessage a')
     if (updateStatusMessageLink) {
       // <if expr="is_win">
       updateStatusMessageLink.href =
diff --git a/browser/resources/settings/brave_overrides/basic_page.ts b/browser/resources/settings/brave_overrides/basic_page.ts
index 03b0e1db6fe9..46f079ee32de 100644
--- a/browser/resources/settings/brave_overrides/basic_page.ts
+++ b/browser/resources/settings/brave_overrides/basic_page.ts
@@ -23,7 +23,11 @@ import '../social_blocking_page/social_blocking_page.js'
 import '../brave_leo_assistant_page/brave_leo_assistant_page.js'
 import '../brave_leo_assistant_page/model_list_section.js'
 
-import {html, RegisterPolymerTemplateModifications, RegisterStyleOverride} from 'chrome://resources/brave/polymer_overriding.js'
+import {
+  html,
+  RegisterPolymerTemplateModifications,
+  RegisterStyleOverride
+} from 'chrome://resources/brave/polymer_overriding.js'
 
 import {loadTimeData} from '../i18n_setup.js'
 
diff --git a/browser/resources/settings/brave_overrides/clear_browsing_data_dialog.ts b/browser/resources/settings/brave_overrides/clear_browsing_data_dialog.ts
index 63352e217a00..0f98fe05bd8e 100644
--- a/browser/resources/settings/brave_overrides/clear_browsing_data_dialog.ts
+++ b/browser/resources/settings/brave_overrides/clear_browsing_data_dialog.ts
@@ -3,13 +3,19 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import {
+  RegisterPolymerComponentReplacement,
+  RegisterPolymerTemplateModifications,
+  RegisterStyleOverride
+} from 'chrome://resources/brave/polymer_overriding.js'
 
-import {RegisterPolymerComponentReplacement, RegisterPolymerTemplateModifications, RegisterStyleOverride} from 'chrome://resources/brave/polymer_overriding.js'
 import {getTrustedHTML} from 'chrome://resources/js/static_types.js'
 import {html} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {BraveSettingsClearBrowsingDataDialogElement} from '../brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.js'
+import {
+  BraveSettingsClearBrowsingDataDialogElement
+} from '../brave_clear_browsing_data_dialog/brave_clear_browsing_data_dialog_behavior.js'
+
 import {loadTimeData} from '../i18n_setup.js'
 
 RegisterStyleOverride(
@@ -33,7 +39,7 @@ RegisterPolymerComponentReplacement(
 )
 
 RegisterPolymerTemplateModifications({
-  'settings-clear-browsing-data-dialog': (templateContent: HTMLTemplateElement) => {
+  'settings-clear-browsing-data-dialog': (templateContent) => {
     // Append On exit tab page.
     const pagesElement = templateContent.querySelector('#pages')
     if (!pagesElement) {
diff --git a/browser/resources/settings/brave_overrides/default_browser_page.ts b/browser/resources/settings/brave_overrides/default_browser_page.ts
index bbd2ffd42259..eeb741aef745 100644
--- a/browser/resources/settings/brave_overrides/default_browser_page.ts
+++ b/browser/resources/settings/brave_overrides/default_browser_page.ts
@@ -3,18 +3,19 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import {RegisterPolymerTemplateModifications} from 'chrome://resources/brave/polymer_overriding.js'
 
-function queryInAllTemplates(element, selector, onFound) {
-  if (!element) {
+function queryInAllTemplates(
+  fragment: DocumentFragment,
+  selector: string,
+  onFound: (element: Element) => void) {
+  if (!fragment) {
     return
   }
-  for (const foundElement of element.querySelectorAll(selector)) {
+  for (const foundElement of fragment.querySelectorAll(selector)) {
     onFound(foundElement)
   }
-  for (const foundTemplate of element.querySelectorAll('template')) {
+  for (const foundTemplate of fragment.querySelectorAll('template')) {
     if (foundTemplate.content) {
       queryInAllTemplates(foundTemplate.content, selector, onFound)
     }
@@ -25,8 +26,9 @@ RegisterPolymerTemplateModifications({
   'settings-default-browser-page': (templateContent) => {
     // Stop both versions thinking they are the first, since this item is added
     // to Brave's "Get Started" section.
-    queryInAllTemplates(templateContent, '.cr-row.first', function (element) {
-      element.classList.remove('first')
+    queryInAllTemplates(templateContent, '.cr-row.first',
+      element => {
+        element.classList.remove('first')
     })
   }
 })
diff --git a/browser/resources/settings/brave_overrides/import_data_dialog.ts b/browser/resources/settings/brave_overrides/import_data_dialog.ts
index 9e98854d4fa1..29d76ed3a010 100644
--- a/browser/resources/settings/brave_overrides/import_data_dialog.ts
+++ b/browser/resources/settings/brave_overrides/import_data_dialog.ts
@@ -3,15 +3,17 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import {
+  html,
+  RegisterPolymerTemplateModifications
+} from 'chrome://resources/brave/polymer_overriding.js'
 
-import {html, RegisterPolymerTemplateModifications} from 'chrome://resources/brave/polymer_overriding.js'
 import {loadTimeData} from 'chrome://resources/js/load_time_data.js'
 
 RegisterPolymerTemplateModifications({
   'settings-import-data-dialog': (templateContent) => {
-    let checkBoxesParent =
-      templateContent.querySelector('#browserSelect').parentElement
+    const checkBoxesParent =
+      templateContent.querySelector('#browserSelect')!.parentElement
     checkBoxesParent.appendChild(html`
       <settings-checkbox id="importDialogExtensions"
         hidden="[[!selected_.extensions]]"
diff --git a/browser/resources/settings/brave_overrides/page_visibility.ts b/browser/resources/settings/brave_overrides/page_visibility.ts
index c85d8625b3aa..90ddaed05f26 100644
--- a/browser/resources/settings/brave_overrides/page_visibility.ts
+++ b/browser/resources/settings/brave_overrides/page_visibility.ts
@@ -3,11 +3,21 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import {loadTimeData} from 'chrome://resources/js/load_time_data.js'
 
-import {loadTimeData} from 'chrome://resources/js/load_time_data.js';
+import {
+  type PageVisibility,
+  pageVisibility as chromiumPageVisibility,
+  resetPageVisibilityForTesting
+} from '../page_visibility.js'
 
-import {pageVisibility as chromiumPageVisibility, resetPageVisibilityForTesting} from '../page_visibility.js'
+// Merge our interface additions with upstream's interface
+declare module '../page_visibility' {
+  export interface PageVisibility {
+    getStarted?: boolean
+    braveWeb3?: boolean
+  }
+}
 
 const alwaysTrue = {
   get: () => true
@@ -65,7 +75,7 @@ function getPageVisibility () {
   return new Proxy(staticProps, {
     get: function(target, prop) {
       if (prop in target) {
-        return target[prop]
+        return target[prop as keyof Object]
       }
       // default to allow, like chromium
       return true
@@ -77,4 +87,4 @@ function getPageVisibility () {
 // override. Even though we are modifying chromium's override, the es module
 // eval timing may result in the unoverridden value being obtained.
 export const pageVisibility = getPageVisibility()
-resetPageVisibilityForTesting(pageVisibility)
+resetPageVisibilityForTesting(pageVisibility as PageVisibility)
diff --git a/browser/resources/settings/brave_overrides/settings_menu.ts b/browser/resources/settings/brave_overrides/settings_menu.ts
index 04d9e4cb492f..a3697957bf18 100644
--- a/browser/resources/settings/brave_overrides/settings_menu.ts
+++ b/browser/resources/settings/brave_overrides/settings_menu.ts
@@ -3,15 +3,17 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import {RegisterPolymerTemplateModifications, RegisterStyleOverride} from 'chrome://resources/brave/polymer_overriding.js'
 import {html} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
 import {loadTimeData} from '../i18n_setup.js'
 import 'chrome://resources/brave/leo.bundle.js'
 
-function createMenuElement(title, href, iconName, pageVisibilitySection) {
+function createMenuElement(
+  title: string,
+  href: string,
+  iconName: string,
+  pageVisibilitySection: string) {
   const menuEl = document.createElement('a')
   if (pageVisibilitySection) {
     menuEl.setAttribute('hidden', `[[!pageVisibility.${pageVisibilitySection}]]`)
@@ -31,7 +33,9 @@ function createMenuElement(title, href, iconName, pageVisibilitySection) {
   return menuEl
 }
 
-function getMenuElement(templateContent, href) {
+function getMenuElement(
+  templateContent: HTMLTemplateElement,
+  href: string) {
   let menuEl = templateContent.querySelector(`a[href="${href}"]`)
   if (!menuEl) {
     // Search templates
@@ -219,27 +223,29 @@ RegisterPolymerTemplateModifications({
     }
 
     // Add 'Get Started' item
-    const peopleEl = getMenuElement(templateContent, '/people')
     const getStartedEl = createMenuElement(
       loadTimeData.getString('braveGetStartedTitle'),
       '/getStarted',
       'rocket',
       'getStarted'
     )
-    peopleEl.insertAdjacentElement('afterend', getStartedEl)
+    const peopleEl = getMenuElement(templateContent, '/people')
+    if (peopleEl) {
+      peopleEl.insertAdjacentElement('afterend', getStartedEl)
+    }
 
     // Move Appearance item
-    const appearanceBrowserEl = getMenuElement(templateContent, '/appearance')
-    getStartedEl.insertAdjacentElement('afterend', appearanceBrowserEl)
-
-    // Add Content item
     const contentEl = createMenuElement(
       loadTimeData.getString('contentSettingsContentSection'),
       '/braveContent',
       'window-content',
       'content',
     )
-    appearanceBrowserEl.insertAdjacentElement('afterend', contentEl)
+    const appearanceBrowserEl = getMenuElement(templateContent, '/appearance')
+    if (appearanceBrowserEl && contentEl) {
+      getStartedEl.insertAdjacentElement('afterend', appearanceBrowserEl)
+      appearanceBrowserEl.insertAdjacentElement('afterend', contentEl)
+    }
 
     // Add Shields item
     const shieldsEl = createMenuElement(
@@ -252,7 +258,9 @@ RegisterPolymerTemplateModifications({
 
     // Add privacy item
     const privacyEl = getMenuElement(templateContent, '/privacy')
-    shieldsEl.insertAdjacentElement('afterend', privacyEl)
+    if (privacyEl && shieldsEl) {
+      shieldsEl.insertAdjacentElement('afterend', privacyEl)
+    }
 
     // Add web3 item
     const web3El = createMenuElement(
@@ -261,7 +269,9 @@ RegisterPolymerTemplateModifications({
       'product-brave-wallet',
       'wallet',
     )
-    privacyEl.insertAdjacentElement('afterend', web3El)
+    if (privacyEl && web3El) {
+      privacyEl.insertAdjacentElement('afterend', web3El)
+    }
 
     // Add leo item
     const leoAssistantEl = createMenuElement(
@@ -283,7 +293,9 @@ RegisterPolymerTemplateModifications({
 
     // Add search item
     const searchEl = getMenuElement(templateContent, '/search')
-    syncEl.insertAdjacentElement('afterend', searchEl)
+    if (searchEl && syncEl) {
+      syncEl.insertAdjacentElement('afterend', searchEl)
+    }
 
     // Add Extensions item
     const extensionEl = createMenuElement(
@@ -292,19 +304,26 @@ RegisterPolymerTemplateModifications({
       'browser-extensions',
       'extensions',
     )
-    searchEl.insertAdjacentElement('afterend', extensionEl)
+    if (extensionEl && searchEl) {
+      searchEl.insertAdjacentElement('afterend', extensionEl)
+    }
 
     // Move autofill to advanced
     const autofillEl = getMenuElement(templateContent, '/autofill')
     const languagesEl = getMenuElement(templateContent, '/languages')
-    languagesEl.insertAdjacentElement('beforebegin', autofillEl)
+    if (autofillEl && languagesEl) {
+      languagesEl.insertAdjacentElement('beforebegin', autofillEl)
+    }
     // Allow Accessibility to be removed :-(
     const a11yEl = getMenuElement(templateContent, '/accessibility')
-    a11yEl.setAttribute('hidden', '[[!pageVisibility.a11y]')
+    if (a11yEl) {
+      a11yEl.setAttribute('hidden', '[[!pageVisibility.a11y]')
+    }
     // Remove extensions link
     const extensionsLinkEl = templateContent.querySelector('#extensionsLink')
     if (!extensionsLinkEl) {
-      console.error('[Brave Settings Overrides] Could not find extensionsLinkEl to remove')
+      console.error('[Settings] Could not find extensionsLinkEl to remove')
+      return
     }
     extensionsLinkEl.remove()
     // Add version number to 'about' link
diff --git a/browser/resources/settings/brave_overrides/settings_ui.ts b/browser/resources/settings/brave_overrides/settings_ui.ts
index e621c57087de..5cc43ec08660 100644
--- a/browser/resources/settings/brave_overrides/settings_ui.ts
+++ b/browser/resources/settings/brave_overrides/settings_ui.ts
@@ -3,22 +3,26 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import {
+  RegisterPolymerComponentBehaviors,
+  RegisterStyleOverride
+} from 'chrome://resources/brave/polymer_overriding.js'
 
-import {RegisterPolymerComponentBehaviors, RegisterStyleOverride} from 'chrome://resources/brave/polymer_overriding.js'
 import {html} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
+import {SettingsUiElement} from '../settings_ui/settings_ui.js'
+
 // TODO: move throttle utility to a chrome://resources module
-function throttle (callback, maxWaitTime = 30) {
+function throttle (callback: () => void, maxWaitTime: number = 30) {
   // Call on first invocation
-  let shouldWait = false;
-  return function (...args) {
+  let shouldWait = false
+  return function (this: unknown, ...args: []) {
     if (!shouldWait) {
-      callback.apply(this, args);
-      shouldWait = true;
+      callback.apply(this, args)
+      shouldWait = true
       setTimeout(function () {
-        shouldWait = false;
-      }, maxWaitTime);
+        shouldWait = false
+      }, maxWaitTime)
     }
   }
 }
@@ -87,25 +91,30 @@ RegisterStyleOverride(
 )
 
 const BraveClearSettingsMenuHighlightBehavior = {
-  ready: function() {
+  ready: function(this: SettingsUiElement) {
     // Clear menu selection after scrolling away.
     // Chromium's menu is not persistant, so does not have
     // this issue.
-    const container = this.$.container
+    const container = this.shadowRoot!.getElementById('container')
     if (!container) {
       console.error('Could not find #container in settings-ui module')
+      return
     }
-    const menu = this.$$('settings-menu')
+    const menu = this.shadowRoot!.querySelector('settings-menu')
     if (!menu) {
       console.error('Could not find settings-menu in settings-ui module')
+      return
     }
-    let onScroll
+    let onScroll: ((event: Event) => void) | null = null
     function stopObservingScroll() {
       if (onScroll) {
-        container.removeEventListener('scroll', onScroll)
+        if (container) {
+          container.removeEventListener('scroll', onScroll)
+        }
         onScroll = null
       }
     }
+    // @ts-expect-error
     window.addEventListener('showing-section', ({ detail: section }) => {
       // Currently showing or about to scroll to `section`. If we're getting
       // further away from section top then section is no longer 'selected'.
@@ -115,14 +124,16 @@ const BraveClearSettingsMenuHighlightBehavior = {
       stopObservingScroll()
       function calcDistance() {
         const sectionScrollTop = section.offsetTop
-        const currentScrollTop = container.scrollTop
+        const currentScrollTop = container?.scrollTop || 0
         return Math.abs(sectionScrollTop - currentScrollTop)
       }
       let distance = calcDistance()
       onScroll = throttle(() => {
         const latestDistance = calcDistance()
         if (latestDistance > distance) {
-          menu.setSelectedUrl_('')
+          if (menu) {
+            (menu as any).setSelectedPath_('')
+          }
           stopObservingScroll()
         } else {
           distance = latestDistance
diff --git a/browser/resources/settings/brave_overrides/site_details.ts b/browser/resources/settings/brave_overrides/site_details.ts
index f632db66302b..72ec79143ce4 100644
--- a/browser/resources/settings/brave_overrides/site_details.ts
+++ b/browser/resources/settings/brave_overrides/site_details.ts
@@ -3,11 +3,10 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import type {SiteDetailsPermissionElement} from '../site_settings/site_details_permission.js'
 
 import {RegisterPolymerTemplateModifications} from 'chrome://resources/brave/polymer_overriding.js'
 import {html} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
-import {getTrustedHTML} from 'chrome://resources/js/static_types.js'
 import {loadTimeData} from '../i18n_setup.js'
 
 import 'chrome://resources/brave/leo.bundle.js'
@@ -20,14 +19,18 @@ RegisterPolymerTemplateModifications({
         content)
 
     if (!loadTimeData.getBoolean('isIdleDetectionFeatureEnabled')) {
-      const idleDetectionItem = templateContent.querySelector('[category="[[contentSettingsTypesEnum_.IDLE_DETECTION]]"]')
+      const idleDetectionItem =
+        templateContent.querySelector<SiteDetailsPermissionElement>(
+          '[category="[[contentSettingsTypesEnum_.IDLE_DETECTION]]"]')
       if (!idleDetectionItem) {
         console.error('[Settings] Couldn\'t find idle detection item')
       } else {
         idleDetectionItem.hidden = true
       }
     }
-    const adsItem = templateContent.querySelector('[category="[[contentSettingsTypesEnum_.ADS]]"]')
+    const adsItem =
+      templateContent.querySelector<SiteDetailsPermissionElement>(
+        '[category="[[contentSettingsTypesEnum_.ADS]]"]')
     if (!adsItem) {
       console.error('[Settings] Couldn\'t find ads item')
     } else {
@@ -40,12 +43,10 @@ RegisterPolymerTemplateModifications({
     } else {
       firstPermissionItem.insertAdjacentHTML(
         'beforebegin',
-        getTrustedHTML`
-          <site-details-permission
-            category="[[contentSettingsTypesEnum_.AUTOPLAY]]"
-            icon="autoplay-on">
-          </site-details-permission>
-        `)
+        `<site-details-permission
+           category="[[contentSettingsTypesEnum_.AUTOPLAY]]"
+           icon="autoplay-on">
+         </site-details-permission>`)
       let curChild = 1
       const autoplaySettings = templateContent.querySelector(
         `div.list-frame > site-details-permission:nth-child(${curChild})`)
@@ -63,14 +64,12 @@ RegisterPolymerTemplateModifications({
       if (isGoogleSignInFeatureEnabled) {
         firstPermissionItem.insertAdjacentHTML(
           'beforebegin',
-          getTrustedHTML`
-            <site-details-permission
-              category="[[contentSettingsTypesEnum_.GOOGLE_SIGN_IN]]"
-              icon="user">
-            </site-details-permission>
-          `)
-        const googleSignInSettings = templateContent.
-          querySelector(`div.list-frame > site-details-permission:nth-child(${curChild})`)
+          `<site-details-permission
+             category="[[contentSettingsTypesEnum_.GOOGLE_SIGN_IN]]"
+             icon="user">
+           </site-details-permission>`)
+        const googleSignInSettings = templateContent.querySelector(
+          `div.list-frame > site-details-permission:nth-child(${curChild})`)
         if (!googleSignInSettings) {
           console.error('[Settings] Couldn\'t find Google signin settings')
         }
@@ -86,12 +85,10 @@ RegisterPolymerTemplateModifications({
       if (isLocalhostAccessFeatureEnabled) {
         firstPermissionItem.insertAdjacentHTML(
           'beforebegin',
-          getTrustedHTML`
-            <site-details-permission
-              category="[[contentSettingsTypesEnum_.LOCALHOST_ACCESS]]"
-              icon="smartphone-desktop">
-            </site-details-permission>
-          `)
+          `<site-details-permission
+             category="[[contentSettingsTypesEnum_.LOCALHOST_ACCESS]]"
+             icon="smartphone-desktop">
+           </site-details-permission>`)
         const localhostAccessSettings = templateContent.querySelector(
           `div.list-frame > site-details-permission:nth-child(${curChild})`)
         if (!localhostAccessSettings) {
@@ -108,14 +105,12 @@ RegisterPolymerTemplateModifications({
       if (isOpenAIChatFromBraveSearchEnabled) {
         firstPermissionItem.insertAdjacentHTML(
           'beforebegin',
-          getTrustedHTML`
-            <site-details-permission
-              category="[[contentSettingsTypesEnum_.BRAVE_OPEN_AI_CHAT]]"
-              icon="user">
-            </site-details-permission>
-          `)
-        const braveAIChatSettings = templateContent.
-          querySelector(`div.list-frame > site-details-permission:nth-child(${curChild})`)
+          `<site-details-permission
+             category="[[contentSettingsTypesEnum_.BRAVE_OPEN_AI_CHAT]]"
+             icon="user">
+           </site-details-permission>`)
+        const braveAIChatSettings = templateContent.querySelector(
+          `div.list-frame > site-details-permission:nth-child(${curChild})`)
         if (!braveAIChatSettings) {
           console.error('[Settings] Couldn\'t find Brave AI chat settings')
         } else {
@@ -129,14 +124,12 @@ RegisterPolymerTemplateModifications({
       if (isNativeBraveWalletEnabled) {
         firstPermissionItem.insertAdjacentHTML(
           'beforebegin',
-          getTrustedHTML`
-            <site-details-permission
-              category="[[contentSettingsTypesEnum_.ETHEREUM]]"
-              icon="ethereum-on">
-            </site-details-permission>
-          `)
-        const ethereumSettings = templateContent.
-          querySelector(`div.list-frame > site-details-permission:nth-child(${curChild})`)
+          `<site-details-permission
+             category="[[contentSettingsTypesEnum_.ETHEREUM]]"
+             icon="ethereum-on">
+           </site-details-permission>`)
+        const ethereumSettings = templateContent.querySelector(
+          `div.list-frame > site-details-permission:nth-child(${curChild})`)
         if (!ethereumSettings) {
           console.error('[Settings] Couldn\'t find Ethereum settings')
         } else {
@@ -146,14 +139,12 @@ RegisterPolymerTemplateModifications({
         curChild++
         firstPermissionItem.insertAdjacentHTML(
           'beforebegin',
-          getTrustedHTML`
-            <site-details-permission
-              category="[[contentSettingsTypesEnum_.SOLANA]]"
-              icon="solana-on">
-            </site-details-permission>
-          `)
-        const solanaSettings = templateContent.
-          querySelector(`div.list-frame > site-details-permission:nth-child(${curChild})`)
+          `<site-details-permission
+             category="[[contentSettingsTypesEnum_.SOLANA]]"
+             icon="solana-on">
+           </site-details-permission>`)
+        const solanaSettings = templateContent.querySelector(
+          `div.list-frame > site-details-permission:nth-child(${curChild})`)
         if (!solanaSettings) {
           console.error('[Settings] Couldn\'t find Solana settings')
         } else {
diff --git a/browser/resources/settings/brave_overrides/site_settings_page.ts b/browser/resources/settings/brave_overrides/site_settings_page.ts
index 193c88b2a3e8..92cecae7c49e 100644
--- a/browser/resources/settings/brave_overrides/site_settings_page.ts
+++ b/browser/resources/settings/brave_overrides/site_settings_page.ts
@@ -3,8 +3,6 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import './config.js'
 
 import {RegisterPolymerComponentReplacement, RegisterPolymerTemplateModifications} from 'chrome://resources/brave/polymer_overriding.js'
@@ -57,56 +55,57 @@ RegisterPolymerTemplateModifications({
 
 RegisterPolymerComponentReplacement(
   'settings-site-settings-page',
-  class BraveComponent extends SettingsSiteSettingsPageElement {
-    static get properties() {
+  class BraveSiteSettingsComponent extends SettingsSiteSettingsPageElement {
+    static override get properties() {
       const properties = SettingsSiteSettingsPageElement.properties
       if (!properties || !properties.lists_ || !properties.lists_.value) {
-        console.error('[Brave Settings Overrides] Could not find polymer lists_ property')
-        return
+        console.error('[Settings] Could not find polymer lists_ property')
       }
       const oldListsGetter = properties.lists_.value
       properties.lists_.value = function () {
-        let lists_ = oldListsGetter()
-        if (!lists_) {
-          console.error('[Brave Settings Overrides] did not get lists_ data')
-          return
-        }
-        if (!lists_.permissionsBasic) {
-          console.error('[Brave Settings Overrides] did not get lists_.permissionsBasic data')
+        const lists = oldListsGetter()
+        if (!lists.permissionsBasic) {
+          console.error('[Settings] did not get lists.permissionsBasic data')
         } else {
-          lists_.permissionsBasic = lists_.permissionsBasic.filter(item => !PERMISSIONS_BASIC_REMOVE_IDS.includes(item.id))
+          lists.permissionsBasic = lists.permissionsBasic.filter(
+            item => !PERMISSIONS_BASIC_REMOVE_IDS.includes(item.id))
         }
-        if (!lists_.contentAdvanced) {
-          console.error('[Brave Settings Overrides] did not get lists_.contentAdvanced data')
+        if (!lists.contentAdvanced) {
+          console.error('[Settings] did not get lists.contentAdvanced data')
         } else {
-          lists_.contentAdvanced = lists_.contentAdvanced.filter(item => !CONTENT_ADVANCED_REMOVE_IDS.includes(item.id))
+          lists.contentAdvanced = lists.contentAdvanced.filter(
+            item => !CONTENT_ADVANCED_REMOVE_IDS.includes(item.id))
         }
-        if (!lists_.permissionsAdvanced) {
-          console.error('[Brave Settings Overrides] did not get lists_.permissionsAdvanced data')
+        if (!lists.permissionsAdvanced) {
+          console.error(
+            '[Settings] did not get lists.permissionsAdvanced data')
         } else {
-          lists_.permissionsAdvanced = lists_.permissionsAdvanced.filter(item => !PERMISSIONS_ADVANCED_REMOVE_IDS.includes(item.id))
+          lists.permissionsAdvanced = lists.permissionsAdvanced.filter(
+            item => !PERMISSIONS_ADVANCED_REMOVE_IDS.includes(item.id))
           if (!loadTimeData.getBoolean('isIdleDetectionFeatureEnabled')) {
-            let indexForIdleDetection = lists_.permissionsAdvanced.findIndex(item => item.id === ContentSettingsTypes.IDLE_DETECTION)
+            const indexForIdleDetection = lists.permissionsAdvanced.findIndex(
+              item => item.id === ContentSettingsTypes.IDLE_DETECTION)
             if (indexForIdleDetection === -1) {
               console.error('Could not find idle detection site settings item')
             } else {
-              lists_.permissionsAdvanced.splice(indexForIdleDetection, 1)
+              lists.permissionsAdvanced.splice(indexForIdleDetection, 1)
             }
           }
-          let indexForAutoplay = lists_.permissionsAdvanced.findIndex(item => item.id === ContentSettingsTypes.AUTOMATIC_DOWNLOADS)
+          let indexForAutoplay = lists.permissionsAdvanced.findIndex(
+            item => item.id === ContentSettingsTypes.AUTOMATIC_DOWNLOADS)
           if (indexForAutoplay === -1) {
             console.error('Could not find automatic downloads site settings item')
           } else {
             indexForAutoplay++
             const autoplayItem = {
               route: routes.SITE_SETTINGS_AUTOPLAY,
-              id: 'autoplay',
+              id: ContentSettingsTypes.AUTOPLAY,
               label: 'siteSettingsAutoplay',
               icon: 'autoplay-on',
               enabledLabel: 'siteSettingsAutoplayAllow',
               disabledLabel: 'siteSettingsAutoplayBlock'
             }
-            lists_.permissionsAdvanced.splice(indexForAutoplay, 0, autoplayItem)
+            lists.permissionsAdvanced.splice(indexForAutoplay, 0, autoplayItem)
             let currentIndex = indexForAutoplay
             const isGoogleSignInFeatureEnabled =
               loadTimeData.getBoolean('isGoogleSignInFeatureEnabled')
@@ -114,13 +113,13 @@ RegisterPolymerComponentReplacement(
               currentIndex++
               const googleSignInItem = {
                 route: routes.SITE_SETTINGS_GOOGLE_SIGN_IN,
-                id: 'googleSignIn',
+                id: ContentSettingsTypes.GOOGLE_SIGN_IN,
                 label: 'siteSettingsGoogleSignIn',
                 icon: 'user',
                 enabledLabel: 'siteSettingsGoogleSignInAsk',
                 disabledLabel: 'siteSettingsGoogleSignInBlock'
               }
-              lists_.permissionsAdvanced.splice(currentIndex, 0,
+              lists.permissionsAdvanced.splice(currentIndex, 0,
                 googleSignInItem)
             }
             const isLocalhostAccessFeatureEnabled =
@@ -129,13 +128,13 @@ RegisterPolymerComponentReplacement(
               currentIndex++
               const localhostAccessItem = {
                 route: routes.SITE_SETTINGS_LOCALHOST_ACCESS,
-                id: 'localhostAccess',
+                id: ContentSettingsTypes.LOCALHOST_ACCESS,
                 label: 'siteSettingsLocalhostAccess',
                 icon: 'smartphone-desktop',
                 enabledLabel: 'siteSettingsLocalhostAccessAsk',
                 disabledLabel: 'siteSettingsLocalhostAccessBlock'
               }
-              lists_.permissionsAdvanced.splice(currentIndex, 0,
+              lists.permissionsAdvanced.splice(currentIndex, 0,
                 localhostAccessItem)
             }
             const isOpenAIChatFromBraveSearchEnabled =
@@ -144,13 +143,13 @@ RegisterPolymerComponentReplacement(
               currentIndex++
               const AIChatItem = {
                 route: routes.SITE_SETTINGS_BRAVE_OPEN_AI_CHAT,
-                id: 'braveOpenAIChat',
+                id: ContentSettingsTypes.BRAVE_OPEN_AI_CHAT,
                 label: 'siteSettingsBraveOpenAIChat',
                 icon: 'product-brave-leo',
                 enabledLabel: 'siteSettingsBraveOpenAIChatAsk',
                 disabledLabel: 'siteSettingsBraveOpenAIChatBlock'
               }
-              lists_.permissionsAdvanced.splice(currentIndex, 0,
+              lists.permissionsAdvanced.splice(currentIndex, 0,
                 AIChatItem)
             }
             const isNativeBraveWalletEnabled =
@@ -159,30 +158,30 @@ RegisterPolymerComponentReplacement(
               currentIndex++
               const ethereumItem = {
                 route: routes.SITE_SETTINGS_ETHEREUM,
-                id: 'ethereum',
+                id: ContentSettingsTypes.ETHEREUM,
                 label: 'siteSettingsEthereum',
                 icon: 'ethereum-on',
                 enabledLabel: 'siteSettingsEthereumAsk',
                 disabledLabel: 'siteSettingsEthereumBlock'
               }
-              lists_.permissionsAdvanced.splice(currentIndex, 0, ethereumItem)
+              lists.permissionsAdvanced.splice(currentIndex, 0, ethereumItem)
               currentIndex++
               const solanaItem = {
                 route: routes.SITE_SETTINGS_SOLANA,
-                id: 'solana',
+                id: ContentSettingsTypes.SOLANA,
                 label: 'siteSettingsSolana',
                 icon: 'solana-on',
                 enabledLabel: 'siteSettingsSolanaAsk',
                 disabledLabel: 'siteSettingsSolanaBlock'
               }
-              lists_.permissionsAdvanced.splice(currentIndex, 0, solanaItem)
+              lists.permissionsAdvanced.splice(currentIndex, 0, solanaItem)
             }
           }
         }
-        lists_.shieldsBasic = [
+        lists.shieldsBasic = [
           {
             route: routes.SITE_SETTINGS_SHIELDS_STATUS,
-            id: 'braveShields',
+            id: ContentSettingsTypes.BRAVE_SHIELDS,
             label: 'siteSettingsShieldsStatus',
             icon: 'shield-done',
             enabledLabel: 'siteSettingsShieldsDescription',
@@ -190,7 +189,7 @@ RegisterPolymerComponentReplacement(
           }
         ]
 
-        return lists_
+        return lists
       }
       return properties
     }
diff --git a/browser/resources/settings/brave_reset_page/brave_reset_profile_dialog_behavior.ts b/browser/resources/settings/brave_reset_page/brave_reset_profile_dialog_behavior.ts
index 107e92ee28da..4e6f21e491a5 100644
--- a/browser/resources/settings/brave_reset_page/brave_reset_profile_dialog_behavior.ts
+++ b/browser/resources/settings/brave_reset_page/brave_reset_profile_dialog_behavior.ts
@@ -3,8 +3,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 const BraveResetProfileDialogBehaviorImpl = {
   ready: function() {
     this.fixSendSettingsCheckbox()
@@ -16,10 +14,11 @@ const BraveResetProfileDialogBehaviorImpl = {
    * @private
    */
   fixSendSettingsCheckbox: function() {
-    this.$.sendSettings.checked = false;
-    this.$.sendSettings.hidden = true;
-    this.$.sendSettings.disabled = true;
-    this.$.sendSettings.parentNode.hidden = true;
+    const sendSettings = (this as any).shadowRoot!.getElementById('sendSettings')
+    sendSettings.checked = false
+    sendSettings.hidden = true
+    sendSettings.disabled = true
+    sendSettings.parentNode.hidden = true
   }
 }
 
diff --git a/browser/resources/settings/brave_routes.ts b/browser/resources/settings/brave_routes.ts
index ba41e5095bf3..3254409c6959 100644
--- a/browser/resources/settings/brave_routes.ts
+++ b/browser/resources/settings/brave_routes.ts
@@ -3,11 +3,9 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import {pageVisibility} from './brave_overrides/page_visibility.js'
 import {loadTimeData} from './i18n_setup.js'
-import {SettingsRoutes} from 'chrome://settings/settings.js'
+import {SettingsRoutes} from './router.js'
 
 export default function addBraveRoutes(r: Partial<SettingsRoutes>) {
   const isGuest = loadTimeData.getBoolean('isGuest')
@@ -44,10 +42,10 @@ export default function addBraveRoutes(r: Partial<SettingsRoutes>) {
   }
   if (pageVisibility.braveWeb3) {
     r.BRAVE_WEB3 = r.BASIC.createSection('/web3', 'web3')
-  }
-  if (pageVisibility.braveWallet) {
-    r.BRAVE_WALLET = r.BRAVE_WEB3.createSection('/wallet', 'wallet')
-    r.BRAVE_WALLET_NETWORKS = r.BRAVE_WALLET.createChild('/wallet/networks')
+    if (pageVisibility.braveWallet) {
+      r.BRAVE_WALLET = r.BRAVE_WEB3.createSection('/wallet', 'wallet')
+      r.BRAVE_WALLET_NETWORKS = r.BRAVE_WALLET.createChild('/wallet/networks')
+    }
   }
   r.BRAVE_NEW_TAB = r.BASIC.createSection('/newTab', 'newTab')
 
diff --git a/browser/resources/settings/brave_sync_page/brave_sync_subpage.ts b/browser/resources/settings/brave_sync_page/brave_sync_subpage.ts
index dc51261f55fb..037ff254ee47 100644
--- a/browser/resources/settings/brave_sync_page/brave_sync_subpage.ts
+++ b/browser/resources/settings/brave_sync_page/brave_sync_subpage.ts
@@ -3,30 +3,39 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
-import 'chrome://resources/cr_elements/cr_icon_button/cr_icon_button.js';
-import 'chrome://resources/cr_elements/icons.html.js';
-import 'chrome://resources/cr_elements/cr_shared_style.css.js';
-import 'chrome://resources/cr_elements/cr_shared_vars.css.js';
-import '../settings_shared.css.js';
-import '../settings_vars.css.js';
-import '../people_page/sync_controls.js';
-import './brave_sync_configure.js';
-import './brave_sync_setup.js';
-
-import {StatusAction, SyncBrowserProxyImpl} from '/shared/settings/people_page/sync_browser_proxy.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {assert} from 'chrome://resources/js/assert.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-
-import {Route, RouteObserverMixin, Router} from '../router.js';
-
-import {BraveSyncBrowserProxy} from './brave_sync_browser_proxy.js';
+import 'chrome://resources/cr_elements/cr_button/cr_button.js'
+import 'chrome://resources/cr_elements/cr_icon_button/cr_icon_button.js'
+import 'chrome://resources/cr_elements/icons.html.js'
+import 'chrome://resources/cr_elements/cr_shared_style.css.js'
+import 'chrome://resources/cr_elements/cr_shared_vars.css.js'
+import '../settings_shared.css.js'
+import '../settings_vars.css.js'
+import '../people_page/sync_controls.js'
+import './brave_sync_configure.js'
+import './brave_sync_setup.js'
+
+import {
+  StatusAction,
+  SyncBrowserProxyImpl
+} from '/shared/settings/people_page/sync_browser_proxy.js'
+
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {assert} from 'chrome://resources/js/assert.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
+
+import {RouteObserverMixin, Router} from '../router.js'
+
+import {
+  BraveSyncBrowserProxy,
+  BraveSyncStatus
+} from './brave_sync_browser_proxy.js'
+
 import {getTemplate} from './brave_sync_subpage.html.js'
 
-const SettingBraveSyncSubpageBase = I18nMixin(RouteObserverMixin(PolymerElement))
+type PageStatus = 'configure' | 'setup' | 'spinner'
+
+const SettingBraveSyncSubpageBase =
+  I18nMixin(RouteObserverMixin(PolymerElement))
 
 class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
   static get is() {
@@ -39,25 +48,20 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
 
   static get properties() {
     return {
-      /**
-       * Current page status
-       * 'configure' | 'setup' | 'spinner'
-       * @private
-       */
       pageStatus_: {
         type: String,
         value: 'configure',
       },
 
       /**
-      * The current sync preferences, supplied by SyncBrowserProxy.
-      * @type {SyncPrefs|undefined}
-      */
+       * The current sync preferences, supplied by SyncBrowserProxy.
+       * @type {SyncPrefs|undefined}
+       */
       syncPrefs: {
         type: Object,
       },
 
-      /** @type {SyncStatus} */
+      /** @type {BraveSyncStatus} */
       syncStatus: {
         type: Object,
       },
@@ -67,28 +71,24 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
         notify: true,
       },
 
-      /** @private */
       syncDisabledByAdmin_: {
         type: Boolean,
         value: false,
         computed: 'computeSyncDisabledByAdmin_(syncStatus.managed)',
       },
 
-      /** @private */
       hasLockedSafeStorage_ : {
         type: Boolean,
         value: false,
         computed: 'computeLockedSafeStorage_(syncStatus)',
       },
 
-      /** @private */
       hasUnlockedSafeStorageCannotDecryptSeed_ : {
         type: Boolean,
         value: false,
         computed: 'computeUnlockedSafeStorageCannotDecryptSeed_(syncStatus)',
       },
 
-      /** @private */
       syncSectionDisabled_: {
         type: Boolean,
         value: false,
@@ -100,58 +100,76 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
     }
   }
 
-  static get observers() {
-    return [
-      'updatePageStatus_(syncStatus.*)'
-    ]
-  }
+  private pageStatus_: PageStatus
+  private syncStatus: BraveSyncStatus
+  private syncCodeDialogType: 'qr' | 'words' | 'input' | 'choose' | null
+  private syncDisabledByAdmin_: boolean
+  private hasLockedSafeStorage_: boolean
+  private hasUnlockedSafeStorageCannotDecryptSeed_: boolean
+  private syncSectionDisabled_: boolean
 
-  /** @private {?SyncBrowserProxy} */
-  browserProxy_ = SyncBrowserProxyImpl.getInstance()
+  private browserProxy_ = SyncBrowserProxyImpl.getInstance()
 
-  braveSyncBrowserProxy_ = BraveSyncBrowserProxy.getInstance();
+  private braveSyncBrowserProxy_: BraveSyncBrowserProxy =
+    BraveSyncBrowserProxy.getInstance()
 
   /**
-  * The beforeunload callback is used to show the 'Leave site' dialog. This
-  * makes sure that the user has the chance to go back and confirm the sync
-  * opt-in before leaving.
-  *
-  * This property is non-null if the user is currently navigated on the sync
-  * settings route.
-  *
-  * @private {?Function}
-  */
-  beforeunloadCallback_ = null
+   * The beforeunload callback is used to show the 'Leave site' dialog. This
+   * makes sure that the user has the chance to go back and confirm the sync
+   * opt-in before leaving.
+   *
+   * This property is non-null if the user is currently navigated on the sync
+   * settings route.
+   */
+  private beforeunloadCallback_: ((e: Event) => void) | null = null
 
   /**
-  * The unload callback is used to cancel the sync setup when the user hits
-  * the browser back button after arriving on the page.
-  * Note: Cases like closing the tab or reloading don't need to be handled,
-  * because they are already caught in |PeopleHandler::~PeopleHandler|
-  * from the C++ code.
-  *
-  * @private {?Function}
-  */
-  unloadCallback_ = null
+   * The unload callback is used to cancel the sync setup when the user hits
+   * the browser back button after arriving on the page.
+   * Note: Cases like closing the tab or reloading don't need to be handled,
+   * because they are already caught in |PeopleHandler::~PeopleHandler|
+   * from the C++ code.
+   */
+  private unloadCallback_: ((e: Event) => void) | null = null
 
   /**
-  * Whether the user completed setup successfully.
-  * @private {boolean}
-  */
-  setupSuccessful_ = false
+   * Whether the user completed setup successfully.
+   */
+  private setupSuccessful_: boolean = false
+
+  static get observers() {
+    return [
+      'updatePageStatus_(syncStatus.*)'
+    ]
+  }
 
-  attached() {
-    super.attached()
+  override currentRouteChanged() {
     const router = Router.getInstance()
-    if (router.getCurrentRoute() == router.getRoutes().BRAVE_SYNC_SETUP) {
+    if (router.getCurrentRoute() === router.getRoutes().BRAVE_SYNC_SETUP) {
       this.onNavigateToPage_()
+      return
     }
+
+    if (router.getRoutes().BRAVE_SYNC_SETUP.
+      contains(router.getCurrentRoute())) {
+      return
+    }
+
+    this.onNavigateAwayFromPage_()
   }
 
-  /** @override */
-  detached() {
+  override connectedCallback() {
+    super.connectedCallback()
     const router = Router.getInstance()
-    if (router.getRoutes().BRAVE_SYNC_SETUP.contains(router.getCurrentRoute())) {
+    if (router.getCurrentRoute() === router.getRoutes().BRAVE_SYNC_SETUP) {
+      this.onNavigateToPage_()
+    }
+  }
+
+  override disconnectedCallback() {
+    const router = Router.getInstance()
+    if (router.getRoutes().BRAVE_SYNC_SETUP.
+      contains(router.getCurrentRoute())) {
       this.onNavigateAwayFromPage_()
     }
 
@@ -164,19 +182,15 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
       this.unloadCallback_ = null
     }
 
-    super.detached()
+    super.disconnectedCallback()
   }
 
-  updatePageStatus_(newValue, oldValue) {
+  private updatePageStatus_(_newValue: PageStatus, _oldValue: PageStatus) {
     const isFirstSetup = this.syncStatus && this.syncStatus.firstSetupInProgress
     this.pageStatus_ = isFirstSetup ? 'setup' : 'configure'
   }
 
-  /**
-  * @return {boolean}
-  * @private
-  */
-  computeSyncSectionDisabled_() {
+  private computeSyncSectionDisabled_(): boolean {
     return this.syncStatus !== undefined &&
       (!!this.syncStatus.disabled ||
         !!this.syncStatus.hasSyncWordsDecryptionError ||
@@ -187,61 +201,29 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
           StatusAction.RETRIEVE_TRUSTED_VAULT_KEYS))
   }
 
-  /**
-  * @return {boolean}
-  * @private
-  */
-  computeSyncDisabledByAdmin_() {
-    return this.syncStatus != undefined && !!this.syncStatus.managed
+  private computeSyncDisabledByAdmin_(): boolean {
+    return !!this.syncStatus?.managed
   }
 
-  /**
-  * @return {boolean}
-  * @private
-  */
-  computeLockedSafeStorage_() {
-    return this.syncStatus != undefined && !!this.syncStatus.hasSyncWordsDecryptionError
-      && !this.syncStatus.isOsEncryptionAvailable
+  private computeLockedSafeStorage_(): boolean {
+    return this.syncStatus &&
+           !!this.syncStatus.hasSyncWordsDecryptionError &&
+           !this.syncStatus.isOsEncryptionAvailable
   }
 
-  /**
-  * @return {boolean}
-  * @private
-  */
-  computeUnlockedSafeStorageCannotDecryptSeed_() {
-    return this.syncStatus != undefined &&
+  private computeUnlockedSafeStorageCannotDecryptSeed_(): boolean {
+    return this.syncStatus &&
       !!this.syncStatus.hasSyncWordsDecryptionError &&
       !!this.syncStatus.isOsEncryptionAvailable
   }
 
-  /** @protected */
-  currentRouteChanged() {
-    const router = Router.getInstance();
-    if (router.getCurrentRoute() == router.getRoutes().BRAVE_SYNC_SETUP) {
-      this.onNavigateToPage_()
-      return
-    }
-
-    if (router.getRoutes().BRAVE_SYNC_SETUP.contains(router.getCurrentRoute())) {
-      return
-    }
-
-    this.onNavigateAwayFromPage_()
+  private isStatus_(expectedPageStatus: PageStatus): boolean {
+    return expectedPageStatus === this.pageStatus_
   }
 
-  /**
-  * @param {!PageStatus} expectedPageStatus
-  * @return {boolean}
-  * @private
-  */
-  isStatus_(expectedPageStatus) {
-    return expectedPageStatus == this.pageStatus_;
-  }
-
-  /** @private */
-  onNavigateToPage_() {
+  private onNavigateToPage_() {
     const router = Router.getInstance()
-    assert(router.getCurrentRoute() == router.getRoutes().BRAVE_SYNC_SETUP)
+    assert(router.getCurrentRoute() === router.getRoutes().BRAVE_SYNC_SETUP)
     if (this.beforeunloadCallback_) {
       return
     }
@@ -254,20 +236,19 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
       // dialog.
       if (this.syncStatus && this.syncStatus.firstSetupInProgress) {
         event.preventDefault()
-        event.returnValue = ''
+        event.returnValue = false
 
         chrome.metricsPrivate.recordUserAction(
           'Signin_Signin_AbortAdvancedSyncSettings')
       }
-    };
+    }
     window.addEventListener('beforeunload', this.beforeunloadCallback_)
 
     this.unloadCallback_ = this.onNavigateAwayFromPage_.bind(this)
     window.addEventListener('unload', this.unloadCallback_)
   }
 
-  /** @private */
-  onNavigateAwayFromPage_() {
+  private onNavigateAwayFromPage_() {
     if (!this.beforeunloadCallback_) {
       return
     }
@@ -288,24 +269,23 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
   }
 
   /**
-  * Called when setup is complete and sync code is set
-  * @private
-  */
-  onSetupSuccess_() {
+   * Called when setup is complete and sync code is set
+   */
+  private onSetupSuccess_() {
     this.setupSuccessful_ = true
     // This navigation causes the firstSetupInProgress flag to be marked as
     // false via `didNavigateAwayFromSyncPage`.
     const router = Router.getInstance()
-    if (router.getCurrentRoute() == router.getRoutes().BRAVE_SYNC_SETUP) {
+    if (router.getCurrentRoute() === router.getRoutes().BRAVE_SYNC_SETUP) {
       router.navigateTo(router.getRoutes().BRAVE_SYNC)
     }
   }
 
   /**
-  * Called when we see that OS safe storage is not locked, but we can't decrypt
-  * the passphrase. So we proposing user to clear data and re-join the chain.
-  */
-  onRejoin_ = async function (e) {
+   * Called when we see that OS safe storage is not locked, but we can't decrypt
+   * the passphrase. So we proposing user to clear data and re-join the chain.
+   */
+  async onRejoin_(_e: Event) {
     const messageText = this.i18n('braveSyncResetConfirmation')
     const shouldReset = confirm(messageText)
     if (!shouldReset) {
@@ -314,7 +294,6 @@ class SettingBraveSyncSubpage extends SettingBraveSyncSubpageBase {
     this.pageStatus_ = 'spinner'
     await this.braveSyncBrowserProxy_.resetSyncChain()
 
-    this.syncCode = undefined;
     this.syncCodeDialogType = 'input'
   }
 }
diff --git a/browser/resources/settings/brave_tor_page/brave_tor_bridges_dialog.ts b/browser/resources/settings/brave_tor_page/brave_tor_bridges_dialog.ts
index f76aa8a44a76..a83554086a7a 100644
--- a/browser/resources/settings/brave_tor_page/brave_tor_bridges_dialog.ts
+++ b/browser/resources/settings/brave_tor_page/brave_tor_bridges_dialog.ts
@@ -3,23 +3,32 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import 'chrome://resources/cr_elements/cr_button/cr_button.js'
+import 'chrome://resources/cr_elements/cr_dialog/cr_dialog.js'
+import 'chrome://resources/cr_elements/cr_input/cr_input.js'
+import '../settings_shared.css.js'
 
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
-import 'chrome://resources/cr_elements/cr_dialog/cr_dialog.js';
-import 'chrome://resources/cr_elements/cr_input/cr_input.js';
-import '../settings_shared.css.js';
-
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import type {CrDialogElement} from 'chrome://resources/cr_elements/cr_dialog/cr_dialog.js'
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
 import {getTemplate} from './brave_tor_bridges_dialog.html.js'
-import {BraveTorBrowserProxyImpl} from './brave_tor_browser_proxy.js'
+
+import {
+  BraveTorBrowserProxy,
+  BraveTorBrowserProxyImpl
+} from './brave_tor_browser_proxy.js'
+
+export interface RequestBridgesDialog {
+  $: {
+    dialog: CrDialogElement,
+  }
+}
 
 const RequestBridgesDialogBase = I18nMixin(PrefsMixin(PolymerElement))
 
-class RequestBridgesDialog extends RequestBridgesDialogBase {
+export class RequestBridgesDialog extends RequestBridgesDialogBase {
   static get is() {
     return 'request-bridges-dialog'
   }
@@ -39,20 +48,28 @@ class RequestBridgesDialog extends RequestBridgesDialogBase {
     }
   }
 
-  browserProxy_ = BraveTorBrowserProxyImpl.getInstance()
+  private status_: string
+  private captcha_: string
+  private captchaResolve_: string
+  private renewDisabled_: boolean
+  private submitDisabled_: boolean
+  public bridges_: Object[]
 
-  ready() {
+  private browserProxy_: BraveTorBrowserProxy =
+    BraveTorBrowserProxyImpl.getInstance()
+
+  override ready() {
     super.ready()
 
     this.status_ = this.i18n('torRequestBridgeDialogWaiting')
-    this.bridges_ = null
+    this.bridges_ = []
     this.requestCaptcha_()
   }
 
-  submitClicked_() {
+  private submitClicked_() {
     this.enableSubmit_(false)
     this.browserProxy_.resolveBridgesCaptcha(this.captchaResolve_).then(
-      (response) => {
+      (response: { bridges: Object[] }) => {
         this.bridges_ = response.bridges
         this.$.dialog.close()
       },
@@ -61,11 +78,11 @@ class RequestBridgesDialog extends RequestBridgesDialogBase {
       })
   }
 
-  cancelClicked_() {
+  private cancelClicked_() {
     this.$.dialog.cancel()
   }
 
-  requestCaptcha_() {
+  private requestCaptcha_() {
     this.captchaResolve_ = ''
     this.status_ = this.i18n('torRequestBridgeDialogWaiting')
     this.captcha_ = ''
@@ -80,11 +97,17 @@ class RequestBridgesDialog extends RequestBridgesDialogBase {
     })
   }
 
-  enableSubmit_(enabled) {
+  private enableSubmit_(enabled: boolean) {
     this.renewDisabled_ = !enabled
     this.submitDisabled_ = !enabled
   }
 }
 
+declare global {
+  interface HTMLElementTagNameMap {
+    'request-bridges-dialog': RequestBridgesDialog
+  }
+}
+
 customElements.define(
   RequestBridgesDialog.is, RequestBridgesDialog)
diff --git a/browser/resources/settings/brave_tor_page/brave_tor_browser_proxy.ts b/browser/resources/settings/brave_tor_page/brave_tor_browser_proxy.ts
index 5fad1aaaa5a4..898d6d59e3a3 100644
--- a/browser/resources/settings/brave_tor_page/brave_tor_browser_proxy.ts
+++ b/browser/resources/settings/brave_tor_page/brave_tor_browser_proxy.ts
@@ -3,8 +3,6 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import { sendWithPromise } from 'chrome://resources/js/cr.js';
 
 // TODO(petemill): Define the expected types instead of using any
@@ -30,7 +28,7 @@ export class BraveTorBrowserProxyImpl implements BraveTorBrowserProxy {
     return sendWithPromise('brave_tor.getBridgesConfig')
   }
 
-  setBridgesConfig(config) {
+  setBridgesConfig(config: any) {
     chrome.send('brave_tor.setBridgesConfig', [config])
   }
 
@@ -38,11 +36,11 @@ export class BraveTorBrowserProxyImpl implements BraveTorBrowserProxy {
     return sendWithPromise('brave_tor.requestBridgesCaptcha')
   }
 
-  resolveBridgesCaptcha(captcha) {
+  resolveBridgesCaptcha(captcha: any) {
     return sendWithPromise('brave_tor.resolveBridgesCaptcha', captcha)
   }
 
-  setTorEnabled(value) {
+  setTorEnabled(value: boolean) {
     chrome.send('brave_tor.setTorEnabled', [value])
   }
 
@@ -58,11 +56,11 @@ export class BraveTorBrowserProxyImpl implements BraveTorBrowserProxy {
     return sendWithPromise('brave_tor.isSnowflakeExtensionAllowed')
   }
 
-  isSnowflakeExtensionEnabled(): Promise<boolean> {
+  isSnowflakeExtensionEnabled() {
     return sendWithPromise('brave_tor.isSnowflakeExtensionEnabled')
   }
 
-  enableSnowflakeExtension(enable): Promise<boolean> {
+  enableSnowflakeExtension(enable: boolean) {
     return sendWithPromise('brave_tor.enableSnowflakeExtension', enable)
   }
 }
diff --git a/browser/resources/settings/brave_tor_page/brave_tor_snowflake_install_failed_dialog.ts b/browser/resources/settings/brave_tor_page/brave_tor_snowflake_install_failed_dialog.ts
index c624b133374f..db862c54db3a 100644
--- a/browser/resources/settings/brave_tor_page/brave_tor_snowflake_install_failed_dialog.ts
+++ b/browser/resources/settings/brave_tor_page/brave_tor_snowflake_install_failed_dialog.ts
@@ -3,18 +3,23 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import 'chrome://resources/cr_elements/cr_button/cr_button.js'
 import 'chrome://resources/cr_elements/cr_dialog/cr_dialog.js'
 import '../settings_shared.css.js'
 
+import type {CrDialogElement} from 'chrome://resources/cr_elements/cr_dialog/cr_dialog.js'
 import { PolymerElement } from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 import { I18nMixin } from 'chrome://resources/cr_elements/i18n_mixin.js'
 import { getTemplate } from './brave_tor_snowflake_install_failed_dialog.html.js'
 
 const DialogBase = I18nMixin(PolymerElement)
 
+interface TorSnowflakeInstallFailedDialog {
+  $: {
+    dialog: CrDialogElement,
+  }
+}
+
 class TorSnowflakeInstallFailedDialog extends DialogBase {
   static get is() {
     return 'tor-snowflake-install-failed-dialog'
@@ -33,5 +38,11 @@ class TorSnowflakeInstallFailedDialog extends DialogBase {
   }
 }
 
+declare global {
+  interface HTMLElementTagNameMap {
+    'tor-snowflake-install-failed-dialog': TorSnowflakeInstallFailedDialog
+  }
+}
+
 customElements.define(
   TorSnowflakeInstallFailedDialog.is, TorSnowflakeInstallFailedDialog)
diff --git a/browser/resources/settings/brave_tor_page/brave_tor_subpage.ts b/browser/resources/settings/brave_tor_page/brave_tor_subpage.ts
index a8a10f8c240a..faaa9bdc04f1 100644
--- a/browser/resources/settings/brave_tor_page/brave_tor_subpage.ts
+++ b/browser/resources/settings/brave_tor_page/brave_tor_subpage.ts
@@ -3,22 +3,35 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // you can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import './brave_tor_bridges_dialog.js'
 import './brave_tor_snowflake_install_failed_dialog.js'
 
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
+import type {CrInputElement} from 'chrome://resources/cr_elements/cr_input/cr_input.js'
+import type {CrRadioGroupElement} from 'chrome://resources/cr_elements/cr_radio_group/cr_radio_group.js'
+import type {SettingsToggleButtonElement} from '../controls/settings_toggle_button.js'
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
 import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js'
 import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
 import {loadTimeData} from '../i18n_setup.js'
 import {RouteObserverMixin} from '../router.js'
 
-import {BraveTorBrowserProxyImpl} from './brave_tor_browser_proxy.js'
+import type {RequestBridgesDialog} from './brave_tor_bridges_dialog.js'
+
+import {
+  BraveTorBrowserProxy,
+  BraveTorBrowserProxyImpl
+} from './brave_tor_browser_proxy.js'
+
 import {getTemplate} from './brave_tor_subpage.html.js'
 
+interface SettingsBraveTorPageElement {
+  $: {
+    bridgesGroup: CrRadioGroupElement,
+  }
+}
+
 const SettingBraveTorPageElementBase =
   I18nMixin(RouteObserverMixin(WebUiListenerMixin(PrefsMixin(PolymerElement))))
 
@@ -156,22 +169,39 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     ]
   }
 
-  browserProxy_ = BraveTorBrowserProxyImpl.getInstance()
-
-  ready() {
+  private loadedConfig_: any
+  private useBridges_: number
+  private builtinBridges_: number
+  private requestedBridges_: string
+  private providedBridges_: string
+  private isUsingBridgesPref_: chrome.settingsPrivate.PrefObject
+  private shouldShowBridgesGroup_: boolean
+  private requestedBridgesPlaceholder_: string
+  private disableTorOption_: boolean
+  private torEnabledPref_: chrome.settingsPrivate.PrefObject
+  private torSnowflakeExtensionEnabledPref_: chrome.settingsPrivate.PrefObject
+  private torSnowflakeExtensionAllowed_: boolean
+  private showRequestBridgesDialog_: boolean
+  private isConfigChanged_: boolean
+  private showTorSnowflakeInstallFailed_: boolean
+
+  private browserProxy_: BraveTorBrowserProxy =
+    BraveTorBrowserProxyImpl.getInstance()
+
+  override ready() {
     super.ready()
 
     if (loadTimeData.getBoolean('shouldExposeElementsForTesting')) {
       window.testing = window.testing || {}
-      window.testing[`torSubpage`] = this.shadowRoot
+      window.testing.torSubpage = this.shadowRoot
     }
 
-    this.browserProxy_.getBridgesConfig().then((config) => {
+    this.browserProxy_.getBridgesConfig().then((config: any) => {
       this.loadedConfig_ = config
       this.isUsingBridgesPref_ = {
         key: '',
         type: chrome.settingsPrivate.PrefType.BOOLEAN,
-        value: config.use_bridges != Usage.NOT_USED,
+        value: config.use_bridges !== Usage.NOT_USED,
       }
       this.useBridges_ = config.use_bridges
       this.builtinBridges_ = config.use_builtin_bridges
@@ -181,46 +211,56 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
 
     // PrefControlMixin checks for a pref being valid, so have to fake it,
     // same as upstream.
-    this.addWebUiListener('tor-enabled-changed', enabled => {
+    this.addWebUiListener('tor-enabled-changed', (enabled: boolean) => {
       this.setTorEnabledPref_(enabled)
     })
-    this.browserProxy_.isTorEnabled().then(enabled => {
+    this.browserProxy_.isTorEnabled().then((enabled: boolean) => {
       this.setTorEnabledPref_(enabled)
     })
-    this.browserProxy_.isTorManaged().then(managed => {
+    this.browserProxy_.isTorManaged().then((managed: boolean) => {
       this.disableTorOption_ = managed
     })
 
     if (loadTimeData.getBoolean('enable_extensions')) {
-      this.browserProxy_.isSnowflakeExtensionAllowed().then(allowed => {
-        this.torSnowflakeExtensionAllowed_ = allowed
+      this.browserProxy_.
+        isSnowflakeExtensionAllowed().then((allowed: boolean) => {
+          this.torSnowflakeExtensionAllowed_ = allowed
+        })
+      this.addWebUiListener('tor-snowflake-extension-enabled',
+        (enabled: boolean) => {
+          this.setTorSnowflakeExtensionEnabledPref_(enabled)
       })
-      this.addWebUiListener('tor-snowflake-extension-enabled', enabled => {
-        this.setTorSnowflakeExtensionEnabledPref_(enabled)
-      })
-      this.browserProxy_.isSnowflakeExtensionEnabled().then(enabled => {
-        this.setTorSnowflakeExtensionEnabledPref_(enabled)
+      this.browserProxy_.
+        isSnowflakeExtensionEnabled().then((enabled:boolean) => {
+          this.setTorSnowflakeExtensionEnabledPref_(enabled)
       })
     }
   }
 
-  onSlotClick_(e) {
-    e.stopPropagation()
+  override currentRouteChanged() {
+    // This is intentional. currentRouteChanged() should be overridden.
   }
 
-  getCurrentConfig_() {
+  private onSlotClick_(event: Event) {
+    event.stopPropagation()
+  }
+
+  private getCurrentConfig_() {
     const bridgesConfig = {
       use_bridges: this.useBridges_,
-      use_builtin_bridges: Number.parseInt(this.builtinBridges_, 10),
-      requested_bridges: this.requestedBridges_.split(/\r\n|\r|\n/).filter(Boolean),
-      provided_bridges: this.providedBridges_.split(/\r\n|\r|\n/).filter(Boolean),
+      use_builtin_bridges: this.builtinBridges_,
+      requested_bridges: this.requestedBridges_.
+        split(/\r\n|\r|\n/).filter(Boolean),
+      provided_bridges: this.providedBridges_.
+        split(/\r\n|\r|\n/).filter(Boolean)
     }
     return bridgesConfig
   }
 
-  computeUseBridgesValue_() {
+  private computeUseBridgesValue_() {
     switch (this.useBridges_) {
       case Usage.NOT_USED:
+      default:
         return ''
       case Usage.USE_BUILT_IN:
         return 'useBuiltIn'
@@ -231,7 +271,7 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     }
   }
 
-  onUseBridgesValueChanged_(event) {
+  private onUseBridgesValueChanged_(event: CustomEvent) {
     switch (event.detail.value) {
       case 'useBuiltIn':
         this.useBridges_ = Usage.USE_BUILT_IN
@@ -245,9 +285,9 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     }
   }
 
-  isUsingBridgesChanged_(value) {
+  private isUsingBridgesChanged_(value: boolean) {
     if (value) {
-      if (this.loadedConfig_.use_bridges != Usage.NOT_USED) {
+      if (this.loadedConfig_.use_bridges !== Usage.NOT_USED) {
         this.useBridges_ = this.loadedConfig_.use_bridges
       } else {
         this.useBridges_ = Usage.USE_BUILT_IN
@@ -257,16 +297,21 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     }
   }
 
-  onBuiltInBridgesSelect_(event) {
-    this.builtinBridges_ = Number(event.target.value)
+  private onBuiltInBridgesSelect_(event: Event) {
+    const target = event.target as CrInputElement
+    if (target.invalid) {
+      return
+    }
+
+    this.builtinBridges_ = Number(target.value)
   }
 
-  computeIsConfigChanged_() {
-    const isObject = (object) => {
+  private computeIsConfigChanged_() {
+    const isObject = (object: any) => {
       return object != null && typeof object === 'object'
     }
 
-    const matches = (object1, object2) => {
+    const matches = (object1: Object, object2: Object) => {
       const keys1 = Object.keys(object1)
       const keys2 = Object.keys(object2)
       if (keys1.length !== keys2.length) {
@@ -274,8 +319,8 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
       }
 
       for (const key of keys1) {
-        const val1 = object1[key]
-        const val2 = object2[key]
+        const val1 = object1[key as keyof Object]
+        const val2 = object2[key as keyof Object]
         const areObjects = isObject(val1) && isObject(val2)
         if ((areObjects && !matches(val1, val2)) ||
           (!areObjects && val1 !== val2)) {
@@ -285,47 +330,48 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
       return true
     }
 
-    if (!this.loadedConfig_ || !this.torEnabledPref_.value)
+    if (!this.loadedConfig_ || !this.torEnabledPref_.value) {
       return false
+    }
 
     const currentConfig = this.getCurrentConfig_()
-    if ((currentConfig.use_bridges == Usage.USE_PROVIDED &&
-      currentConfig.provided_bridges.length == 0) ||
-      (currentConfig.use_bridges == Usage.USE_REQUESTED &&
-        currentConfig.requested_bridges.length == 0)) {
+    if ((currentConfig.use_bridges === Usage.USE_PROVIDED &&
+      currentConfig.provided_bridges.length === 0) ||
+      (currentConfig.use_bridges === Usage.USE_REQUESTED &&
+        currentConfig.requested_bridges.length === 0)) {
       return false
     }
 
     return !matches(this.getCurrentConfig_(), this.loadedConfig_)
   }
 
-  computeRequestedBridgesPlaceholder_() {
-    if (this.useBridges_ == Usage.USE_REQUESTED) {
+  private computeRequestedBridgesPlaceholder_() {
+    if (this.useBridges_ === Usage.USE_REQUESTED) {
       return this.i18n('torRequestedBridgesPlaceholder')
     }
     return ''
   }
 
-  computeProvidedBridgesPlaceholder_() {
-    if (this.useBridges_ == Usage.USE_PROVIDED) {
+  private computeProvidedBridgesPlaceholder_() {
+    if (this.useBridges_ === Usage.USE_PROVIDED) {
       return this.i18n('torProvidedBridgesPlaceholder')
     }
     return ''
   }
 
-  computeShouldShowBridgesGroup_() {
+  private computeShouldShowBridgesGroup_() {
     return this.isUsingBridgesPref_.value && this.torEnabledPref_.value
   }
 
-  builtInTypeEqual_(item, selection) {
+  private builtInTypeEqual_(item: any, selection: any) {
     return item === selection
   }
 
-  usageEqual_(usage, current) {
+  private usageEqual_(usage: any, current: any) {
     return usage === current
   }
 
-  setTorEnabledPref_(enabled) {
+  private setTorEnabledPref_(enabled: boolean) {
     const pref = {
       key: '',
       type: chrome.settingsPrivate.PrefType.BOOLEAN,
@@ -334,36 +380,38 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     this.torEnabledPref_ = pref
   }
 
-  onTorEnabledChange_(e) {
-    e.stopPropagation()
-    this.browserProxy_.setTorEnabled(e.target.checked)
+  private onTorEnabledChange_(event: Event) {
+    event.stopPropagation()
+    this.browserProxy_.
+      setTorEnabled((event.target as SettingsToggleButtonElement).checked)
   }
 
-  onUseBridgesChange_(e) {
-    e.stopPropagation()
+  private onUseBridgesChange_(event: Event) {
+    event.stopPropagation()
     setTimeout(() => {
       this.$.bridgesGroup.scrollIntoView()
     })
   }
 
-  setBridgesConfig_(e) {
-    e.stopPropagation()
+  private setBridgesConfig_(event: Event) {
+    event.stopPropagation()
     this.loadedConfig_ = this.getCurrentConfig_()
     this.browserProxy_.setBridgesConfig(this.loadedConfig_)
   }
 
-  requestBridges_() {
+  private requestBridges_() {
     this.showRequestBridgesDialog_ = true
   }
 
-  showRequestBridgesDialogClosed_(event) {
+  private showRequestBridgesDialogClosed_(event: Event) {
     this.showRequestBridgesDialog_ = false
-    if (event.currentTarget.bridges_) {
-      this.requestedBridges_ = event.currentTarget.bridges_.join('\n')
+    const currentTarget = event.currentTarget as RequestBridgesDialog
+    if (currentTarget.bridges_) {
+      this.requestedBridges_ = currentTarget.bridges_.join('\n')
     }
   }
 
-  setTorSnowflakeExtensionEnabledPref_(enabled: boolean) {
+  private setTorSnowflakeExtensionEnabledPref_(enabled: boolean) {
     const pref = {
       key: '',
       type: chrome.settingsPrivate.PrefType.BOOLEAN,
@@ -372,9 +420,10 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
     this.torSnowflakeExtensionEnabledPref_ = pref
   }
 
-  onTorSnowflakeExtensionChange_(e: Event) {
-    e.stopPropagation()
-    this.browserProxy_.enableSnowflakeExtension(e.target.checked).
+  private onTorSnowflakeExtensionChange_(event: Event) {
+    event.stopPropagation()
+    const enabled = (event.target as SettingsToggleButtonElement).checked
+    this.browserProxy_.enableSnowflakeExtension(enabled).
       catch((reason: String) => {
         console.log(reason)
         this.setTorSnowflakeExtensionEnabledPref_(false)
@@ -382,13 +431,9 @@ class SettingsBraveTorPageElement extends SettingBraveTorPageElementBase {
       })
   }
 
-  torSnowflakeInstallFailedDialogClosed_() {
+  private torSnowflakeInstallFailedDialogClosed_() {
     this.showTorSnowflakeInstallFailed_ = false
   }
-
-  currentRouteChanged() {
-    // This is intentional. currentRouteChanged() should be overridden.
-  }
 }
 
 customElements.define(
diff --git a/browser/resources/settings/brave_wallet_page/brave_wallet_browser_proxy.ts b/browser/resources/settings/brave_wallet_page/brave_wallet_browser_proxy.ts
index a953363a3172..e555bd220c22 100644
--- a/browser/resources/settings/brave_wallet_page/brave_wallet_browser_proxy.ts
+++ b/browser/resources/settings/brave_wallet_page/brave_wallet_browser_proxy.ts
@@ -1,7 +1,7 @@
 /* Copyright (c) 2021 The Brave Authors. All rights reserved.
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * you can obtain one at https://mozilla.org/MPL/2.0/. */
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 import {sendWithPromise} from 'chrome://resources/js/cr.js'
 
@@ -76,10 +76,6 @@ export class BraveWalletBrowserProxyImpl implements BraveWalletBrowserProxy {
     chrome.send('resetTransactionInfo', [])
   }
 
-  setBraveWalletEnabled (value: boolean) {
-    chrome.send('setBraveWalletEnabled', [value])
-  }
-
   getNetworksList (coin: number) {
     return sendWithPromise('getNetworksList', coin)
   }
diff --git a/browser/resources/settings/brave_wallet_page/brave_wallet_page.ts b/browser/resources/settings/brave_wallet_page/brave_wallet_page.ts
index 8b7c1b3032bd..864a5f14e48e 100644
--- a/browser/resources/settings/brave_wallet_page/brave_wallet_page.ts
+++ b/browser/resources/settings/brave_wallet_page/brave_wallet_page.ts
@@ -3,21 +3,37 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // You can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import './wallet_networks_subpage.js'
 
-import 'chrome://resources/cr_elements/cr_input/cr_input.js';
-import './wallet_networks_subpage.js';
+import type {CrInputElement} from 'chrome://resources/cr_elements/cr_input/cr_input.js'
 
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {RouteObserverMixin, Router} from '../router.js';
+import {RouteObserverMixin, Router} from '../router.js'
+
+import {
+  BraveWalletBrowserProxy,
+  BraveWalletBrowserProxyImpl,
+  type Option,
+  type SolanaProvider
+} from './brave_wallet_browser_proxy.js'
 
-import {BraveWalletBrowserProxyImpl} from './brave_wallet_browser_proxy.js';
 import {getTemplate} from './brave_wallet_page.html.js'
 
+interface SettingsBraveWalletPage {
+  $: {
+    walletAutoLockMinutes: CrInputElement
+  }
+}
+
+interface CurrencyType {
+  name: string,
+  value: string,
+}
+
 const SettingsBraveWalletPageBase =
   WebUiListenerMixin(PrefsMixin(I18nMixin(RouteObserverMixin(PolymerElement))))
 
@@ -32,12 +48,47 @@ class SettingsBraveWalletPage extends SettingsBraveWalletPageBase {
 
   static get properties() {
     return {
+      ethereum_provider_options_: {
+        type: Array,
+        value() {
+          return []
+        }
+      },
+
+      solana_provider_options_: {
+        type: Array,
+        value() {
+          return []
+        }
+      },
+
+      transaction_simulation_opt_in_options_: {
+        type: Array,
+        value() {
+          return []
+        }
+      },
+
+      cryptocurrency_list_: {
+        type: Array,
+        value() {
+          return []
+        }
+      },
+
+      currency_list_: {
+        type: Array,
+        value() {
+          return []
+        }
+      },
+
       isNativeWalletEnabled_: {
         type: Boolean
       },
 
       isNetworkEditor_: {
-        type: Number,
+        type: Boolean,
         value: false,
       },
 
@@ -57,126 +108,130 @@ class SettingsBraveWalletPage extends SettingsBraveWalletPageBase {
         type: Boolean,
         value: false,
       },
-
-
     }
   }
 
-  browserProxy_ = BraveWalletBrowserProxyImpl.getInstance()
+  private ethereum_provider_options_: Option[]
+  private solana_provider_options_: SolanaProvider[]
+  private transaction_simulation_opt_in_options_: Option[]
+  private cryptocurrency_list_: CurrencyType[]
+  private currency_list_: CurrencyType[]
+  private isNativeWalletEnabled_: boolean
+  private isNetworkEditor_: boolean
+  private isTransactionSimulationsFeatureEnabled: boolean
+  private isPrivateWindowsEnabled_: chrome.settingsPrivate.PrefObject<boolean>
+  private showRestartToast_: boolean
 
-  ready() {
+  private browserProxy_: BraveWalletBrowserProxy =
+    BraveWalletBrowserProxyImpl.getInstance()
+
+  override ready() {
     super.ready()
     this.browserProxy_.getWeb3ProviderList().then(list => {
       // TODO(petemill): provide wallets type
       this.ethereum_provider_options_ = JSON.parse(list)
-    });
+    })
     this.browserProxy_.getSolanaProviderOptions().then(list => {
       // TODO(petemill): provide wallets type
       this.solana_provider_options_ = list
-    });
+    })
     this.browserProxy_.isNativeWalletEnabled().then(val => {
       this.isNativeWalletEnabled_ = val
-    });
+    })
     this.browserProxy_.getAutoLockMinutes().then(val => {
-      this.$.walletAutoLockMinutes.value = val
+      this.$.walletAutoLockMinutes.value = String(val)
     })
     this.browserProxy_.isTransactionSimulationsFeatureEnabled().then(val => {
       this.isTransactionSimulationsFeatureEnabled = val
-    });
+    })
     this.browserProxy_.getTransactionSimulationOptInStatusOptions()
       .then(list => {
         this.transaction_simulation_opt_in_options_ = list
-      });
+      })
     this.browserProxy_.getWalletInPrivateWindowsEnabled().then((val) => {
       this.isPrivateWindowsEnabled_ = {
         key: '',
         type: chrome.settingsPrivate.PrefType.BOOLEAN,
         value: val,
       }
-    });
+    })
 
     this.cryptocurrency_list_ = [
-      { value: "BTC" },
-      { value: "ETH" },
-      { value: "LTC" },
-      { value: "BCH" },
-      { value: "BNB" },
-      { value: "EOS" },
-      { value: "XRP" },
-      { value: "XLM" },
-      { value: "LINK" },
-      { value: "DOT" },
-      { value: "YFI" }
+      { value: 'BTC', name: 'BTC' },
+      { value: 'ETH', name: 'ETH' },
+      { value: 'LTC', name: 'LTC' },
+      { value: 'BCH', name: 'BCH' },
+      { value: 'BNB', name: 'BNB' },
+      { value: 'EOS', name: 'EOS' },
+      { value: 'XRP', name: 'XRP' },
+      { value: 'XLM', name: 'XLM' },
+      { value: 'LINK', name: 'LINK' },
+      { value: 'DOT', name: 'DOT' },
+      { value: 'YFI', name: 'YFI' }
     ]
-    this.cryptocurrency_list_.every((x) => x.name = x.value);
 
     this.currency_list_ = [
-      { value: 'AED' },
-      { value: 'ARS' },
-      { value: 'AUD' },
-      { value: 'BDT' },
-      { value: 'BHD' },
-      { value: 'BMD' },
-      { value: 'BRL' },
-      { value: 'CAD' },
-      { value: 'CHF' },
-      { value: 'CLP' },
-      { value: 'CZK' },
-      { value: 'DKK' },
-      { value: 'EUR' },
-      { value: 'GBP' },
-      { value: 'HKD' },
-      { value: 'HUF' },
-      { value: 'IDR' },
-      { value: 'ILS' },
-      { value: 'INR' },
-      { value: 'JPY' },
-      { value: 'KRW' },
-      { value: 'KWD' },
-      { value: 'LKR' },
-      { value: 'MMK' },
-      { value: 'MXN' },
-      { value: 'MYR' },
-      { value: 'NGN' },
-      { value: 'NOK' },
-      { value: 'NZD' },
-      { value: 'PHP' },
-      { value: 'PKR' },
-      { value: 'PLN' },
-      { value: 'RUB' },
-      { value: 'SAR' },
-      { value: 'SEK' },
-      { value: 'SGD' },
-      { value: 'THB' },
-      { value: 'TRY' },
-      { value: 'TWD' },
-      { value: 'UAH' },
-      { value: 'USD' },
-      { value: 'VEF' },
-      { value: 'VND' },
-      { value: 'ZAR' },
-      { value: 'XAG' },
-      { value: 'XAU' },
-      { value: 'XDR' }
+      { value: 'AED', name: 'AED' },
+      { value: 'ARS', name: 'ARS' },
+      { value: 'AUD', name: 'AUD' },
+      { value: 'BDT', name: 'BDT' },
+      { value: 'BHD', name: 'BHD' },
+      { value: 'BMD', name: 'BMD' },
+      { value: 'BRL', name: 'BRL' },
+      { value: 'CAD', name: 'CAD' },
+      { value: 'CHF', name: 'CHF' },
+      { value: 'CLP', name: 'CLP' },
+      { value: 'CZK', name: 'CZK' },
+      { value: 'DKK', name: 'DKK' },
+      { value: 'EUR', name: 'EUR' },
+      { value: 'GBP', name: 'GBP' },
+      { value: 'HKD', name: 'HKD' },
+      { value: 'HUF', name: 'HUF' },
+      { value: 'IDR', name: 'IDR' },
+      { value: 'ILS', name: 'ILS' },
+      { value: 'INR', name: 'INR' },
+      { value: 'JPY', name: 'JPY' },
+      { value: 'KRW', name: 'KRW' },
+      { value: 'KWD', name: 'KWD' },
+      { value: 'LKR', name: 'LKR' },
+      { value: 'MMK', name: 'MMK' },
+      { value: 'MXN', name: 'MXN' },
+      { value: 'MYR', name: 'MYR' },
+      { value: 'NGN', name: 'MGN' },
+      { value: 'NOK', name: 'NOK' },
+      { value: 'NZD', name: 'NZD' },
+      { value: 'PHP', name: 'PHP' },
+      { value: 'PKR', name: 'PKR' },
+      { value: 'PLN', name: 'PLN' },
+      { value: 'RUB', name: 'RUB' },
+      { value: 'SAR', name: 'SAR' },
+      { value: 'SEK', name: 'SEK' },
+      { value: 'SGD', name: 'SGD' },
+      { value: 'THB', name: 'THB' },
+      { value: 'TRY', name: 'TRY' },
+      { value: 'TWD', name: 'TWD' },
+      { value: 'UAH', name: 'UAH' },
+      { value: 'USD', name: 'USD' },
+      { value: 'VEF', name: 'VEF' },
+      { value: 'VND', name: 'VND' },
+      { value: 'ZAR', name: 'ZAR' },
+      { value: 'XAG', name: 'XAG' },
+      { value: 'XAU', name: 'XAU' },
+      { value: 'XDR', name: 'XDR' }
     ]
-    this.currency_list_.every((x) => x.name = x.value);
-  }
-
-  onBraveWalletEnabledChange_() {
-    this.browserProxy_.setBraveWalletEnabled(this.$.braveWalletEnabled.checked);
   }
 
-  isNetworkEditorRoute() {
-    const router = Router.getInstance();
-    return (router.getCurrentRoute() == router.getRoutes().BRAVE_WALLET_NETWORKS);
+  override currentRouteChanged() {
+    this.isNetworkEditor_ = this.isNetworkEditorRoute()
   }
 
-  /** @protected */
-  currentRouteChanged() {
-    this.isNetworkEditor_ = this.isNetworkEditorRoute()
+  private isNetworkEditorRoute() {
+    const router = Router.getInstance()
+    return (router.getCurrentRoute() ===
+      router.getRoutes().BRAVE_WALLET_NETWORKS)
   }
 
-  onInputAutoLockMinutes_() {
+  private onInputAutoLockMinutes_() {
     let value = Number(this.$.walletAutoLockMinutes.value)
     if (Number.isNaN(value) || value < 1 || value > 10080) {
       return
@@ -184,30 +239,32 @@ class SettingsBraveWalletPage extends SettingsBraveWalletPageBase {
     this.setPrefValue('brave.wallet.auto_lock_minutes', value)
   }
 
-  onWalletNetworksEditorClick_() {
-    const router = Router.getInstance();
-    router.navigateTo(router.getRoutes().BRAVE_WALLET_NETWORKS);
+  private onWalletNetworksEditorClick_() {
+    const router = Router.getInstance()
+    router.navigateTo(router.getRoutes().BRAVE_WALLET_NETWORKS)
   }
 
-  onResetWallet_() {
-    var message = this.i18n('walletResetConfirmation')
-    if (window.prompt(message) !== this.i18n('walletResetConfirmationPhrase'))
+  private onResetWallet_() {
+    const message = this.i18n('walletResetConfirmation')
+    if (window.prompt(message) !== this.i18n('walletResetConfirmationPhrase')) {
       return
+    }
     this.browserProxy_.resetWallet()
     window.alert(this.i18n('walletResetConfirmed'))
   }
 
-  onResetTransactionInfo_() {
-    var message = this.i18n('walletResetTransactionInfoConfirmation')
-    if (window.prompt(message) !== this.i18n('walletResetConfirmationPhrase'))
+  private onResetTransactionInfo_() {
+    const message = this.i18n('walletResetTransactionInfoConfirmation')
+    if (window.prompt(message) !== this.i18n('walletResetConfirmationPhrase')) {
       return
+    }
     this.browserProxy_.resetTransactionInfo()
     window.alert(this.i18n('walletResetTransactionInfoConfirmed'))
   }
 
-  onPrivateWindowsEnabled_() {
+  private onPrivateWindowsEnabled_() {
     // Toggle the setting switch UI, but don't actually update the pref.
-    const pref = {
+    const pref: chrome.settingsPrivate.PrefObject = {
       key: '',
       type: chrome.settingsPrivate.PrefType.BOOLEAN,
       value: !this.isPrivateWindowsEnabled_.value,
@@ -216,7 +273,7 @@ class SettingsBraveWalletPage extends SettingsBraveWalletPageBase {
     this.updateRestartToast_()
   }
 
-  updateRestartToast_() {
+  private updateRestartToast_() {
     // Show restart toast if current private windows pref
     // value does not match UI switch.
     this.browserProxy_.getWalletInPrivateWindowsEnabled().then(enabled => {
@@ -228,7 +285,7 @@ class SettingsBraveWalletPage extends SettingsBraveWalletPageBase {
     })
   }
 
-  applyPrefChangesAndRestart(e) {
+  private applyPrefChangesAndRestart(e: Event) {
     this.browserProxy_.setWalletInPrivateWindowsEnabled(
       this.isPrivateWindowsEnabled_.value
     ).then(() => {
diff --git a/browser/resources/settings/brave_wallet_page/wallet_networks_list.ts b/browser/resources/settings/brave_wallet_page/wallet_networks_list.ts
index d420d259d8cb..eada6363aef7 100644
--- a/browser/resources/settings/brave_wallet_page/wallet_networks_list.ts
+++ b/browser/resources/settings/brave_wallet_page/wallet_networks_list.ts
@@ -3,15 +3,21 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import 'chrome://resources/cr_elements/cr_button/cr_button.js'
+import './add_wallet_network_dialog.js'
 
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
-import './add_wallet_network_dialog.js';
+import {
+  BraveWalletBrowserProxyImpl,
+  type NetworkInfo,
+} from './brave_wallet_browser_proxy.js'
 
-import { BraveWalletBrowserProxyImpl } from './brave_wallet_browser_proxy.js';
-import { I18nMixin } from 'chrome://resources/cr_elements/i18n_mixin.js';
-import { PolymerElement } from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-import { BaseMixin } from '../base_mixin.js';
+import type {CrActionMenuElement} from 'chrome://resources/cr_elements/cr_action_menu/cr_action_menu.js'
+import type {CrLazyRenderElement} from 'chrome://resources/cr_elements/cr_lazy_render/cr_lazy_render.js'
+import type {IronListElement} from 'chrome://resources/polymer/v3_0/iron-list/iron-list.js'
+
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
+import {BaseMixin} from '../base_mixin.js'
 import {getTemplate} from './wallet_networks_list.html.js'
 import {loadTimeData} from '../i18n_setup.js'
 
@@ -55,7 +61,13 @@ class SettingsWalletNetworksList extends SettingsWalletNetworksListBase {
       customNetworks: {
         type: Array,
         value() {
-          return [];
+          return []
+        },
+      },
+      hiddenNetworks: {
+        type: Array,
+        value() {
+          return []
         },
       },
       showAddWalletNetworkDialog_: {
@@ -85,73 +97,85 @@ class SettingsWalletNetworksList extends SettingsWalletNetworksListBase {
     }
   }
 
-  browserProxy_ = BraveWalletBrowserProxyImpl.getInstance()
+  private addNewAllowed: boolean
+  private coin: number
+  private listTitle: string
+  private networks: NetworkInfo[]
+  private knownNetworks: string[]
+  private customNetworks: string[]
+  private hiddenNetworks: string[]
+  private showAddWalletNetworkDialog_: boolean
+  private selectedNetwork: NetworkInfo | null
+  private defaultNetwork: string
+  private isDefaultNetwork: boolean
+  private canRemoveNetwork: boolean
+  private canResetNetwork: boolean
 
-  notifyKeylist() {
-    const keysList =
-    /** @type {IronListElement} */ (this.$$('#networksList'))
-    if (keysList) {
-      keysList.notifyResize()
-    }
-  }
+  browserProxy_ = BraveWalletBrowserProxyImpl.getInstance()
 
-  /*++++++
-  * @override */
-  ready() {
+  override ready() {
     super.ready()
     this.updateNetworks()
   }
 
-  /** @override */
-  connectedCallback() {
-    super.connectedCallback();
+  override connectedCallback() {
+    super.connectedCallback()
     if (loadTimeData.getBoolean('shouldExposeElementsForTesting')) {
       window.testing = window.testing || {}
       window.testing[`walletNetworks${this.coin}`] = this.shadowRoot
     }
   }
 
-  /** @override */
-  disconnectedCallback() {
-    super.disconnectedCallback();
+  override disconnectedCallback() {
+    super.disconnectedCallback()
     if (loadTimeData.getBoolean('shouldExposeElementsForTesting')) {
       delete window.testing[`walletNetworks${this.coin}`]
     }
   }
 
-  getNetworkItemClass(item) {
+  private notifyKeylist() {
+    const keysList = this.$$<IronListElement>('#networksList')
+    if (keysList) {
+      keysList.notifyResize()
+    }
+  }
+
+  private getNetworkItemClass(item: NetworkInfo) {
     if (this.checkIsDefaultNetwork(item.chainId)) {
       return "flex cr-padded-text default-network"
     }
     return "flex cr-padded-text"
   }
 
-  getHideButtonClass(hiddenNetworks, item) {
-    if (!this.checkIsDefaultNetwork(item.chainId) && hiddenNetworks.indexOf(item.chainId) > -1) {
+  private getHideButtonClass(hiddenNetworks: string[], item: NetworkInfo) {
+    if (!this.checkIsDefaultNetwork(item.chainId) &&
+        hiddenNetworks.includes(item.chainId)) {
       return "hide-network-button icon-visibility-off"
     }
     return "hide-network-button icon-visibility"
   }
 
-  getDataTestId(item) {
+  private getDataTestId(item: NetworkInfo) {
     return 'chain-' + item.chainId
   }
 
-  checkIsDefaultNetwork(chainId) {
+  private checkIsDefaultNetwork(chainId: string) {
     return chainId === this.defaultNetwork
   }
 
-  canRemoveNetwork_(item) {
-    if (this.checkIsDefaultNetwork(item.chainId)) return false
+  private canRemoveNetwork_(item: NetworkInfo) {
+    if (this.checkIsDefaultNetwork(item.chainId)) {
+      return false
+    }
 
-    return this.knownNetworks.indexOf(item.chainId) == -1
+    return !this.knownNetworks.includes(item.chainId)
   }
 
-  canHideNetwork_(item) {
-    return !this.checkIsDefaultNetwork(item.chainId);
+  private canHideNetwork_(item: NetworkInfo) {
+    return !this.checkIsDefaultNetwork(item.chainId)
   }
 
-  eyeButtonTitle_(item) {
+  private eyeButtonTitle_(item: NetworkInfo) {
     if (this.checkIsDefaultNetwork(item.chainId)) {
       return this.i18n('walletDefaultNetworkIsAlwaysVisible')
     }
@@ -159,76 +183,92 @@ class SettingsWalletNetworksList extends SettingsWalletNetworksListBase {
     return this.i18n('walletShowHideNetwork')
   }
 
-  canResetNetwork_(item) {
+  private canResetNetwork_(item: NetworkInfo) {
     return (
-      this.knownNetworks.indexOf(item.chainId) > -1 &&
-      this.customNetworks.indexOf(item.chainId) > -1
+      this.knownNetworks.includes(item.chainId) &&
+      this.customNetworks.includes(item.chainId)
     )
   }
 
-  hideNativeCurrencyInfo(item) {
+  private hideNativeCurrencyInfo(item: NetworkInfo) {
     return !item.nativeCurrency || item.nativeCurrency.name.trim() === ''
   }
 
-  getItemDescritionText(item) {
+  private getItemDescritionText(item: NetworkInfo) {
     const url = (item.rpcUrls && item.rpcUrls[item.activeRpcEndpointIndex])
       ? item.rpcUrls[item.activeRpcEndpointIndex]
       : ''
     return item.chainId + ' ' + url
   }
 
-  onSetAsDefaultActionTapped_(event) {
+  private onSetAsDefaultActionTapped_(_event: Event) {
+    if (!this.selectedNetwork) {
+      return
+    }
     const chainId = this.selectedNetwork.chainId
-    this.selectedNetwork = {}
+    this.selectedNetwork = null
     this.browserProxy_.setDefaultNetwork(chainId, this.coin).
-      then(success => { this.updateNetworks() })
-    this.$$('cr-action-menu').close();
+      then((_success) => {
+        this.updateNetworks()
+      })
+    this.$$<CrActionMenuElement>('cr-action-menu')!.close()
   }
 
-  onDeleteActionTapped_(event) {
+  private onDeleteActionTapped_(_event: Event) {
+    if (!this.selectedNetwork) {
+      return
+    }
     const chainId = this.selectedNetwork.chainId
     const chainName = this.selectedNetwork.chainName
-    this.selectedNetwork = {}
-    this.$$('cr-action-menu').close();
+    this.selectedNetwork = null
+    this.$$<CrActionMenuElement>('cr-action-menu')!.close()
     if (this.checkIsDefaultNetwork(chainId)) {
       this.updateNetworks()
       return
     }
-    var message = this.i18n('walletDeleteNetworkConfirmation', chainName)
-    if (!window.confirm(message))
+    const message = this.i18n('walletDeleteNetworkConfirmation', chainName)
+    if (!window.confirm(message)) {
       return
+    }
 
     this.browserProxy_.removeChain(chainId, this.coin).
-      then(success => { this.updateNetworks() })
+      then((_success: boolean) => {
+        this.updateNetworks()
+      })
   }
 
-  onResetActionTapped_(event) {
+  private onResetActionTapped_(_event: Event) {
+    if (!this.selectedNetwork) {
+      return
+    }
     const chainId = this.selectedNetwork.chainId
     const chainName = this.selectedNetwork.chainName
-    this.selectedNetwork = {}
-    this.$$("cr-action-menu").close()
-    var message = this.i18n("walletResetNetworkConfirmation", chainName)
-    if (!window.confirm(message)) return
+    this.selectedNetwork = null
+    this.$$<CrActionMenuElement>("cr-action-menu")!.close()
+    const message = this.i18n("walletResetNetworkConfirmation", chainName)
+    if (!window.confirm(message)) {
+      return
+    }
 
-    this.browserProxy_.resetChain(chainId, this.coin).then((success) => {
+    this.browserProxy_.resetChain(chainId, this.coin).then((_success) => {
       this.updateNetworks()
     })
   }
 
-  onAddNetworkTap_(item) {
+  private onAddNetworkTap_(_item: NetworkInfo) {
     this.showAddWalletNetworkDialog_ = true
   }
 
-  onItemDoubleClick(event) {
+  private onItemDoubleClick(event: Event&{model: {item: NetworkInfo}}) {
     this.selectedNetwork = event.model.item
     this.showAddWalletNetworkDialog_ = true
   }
 
-  onEmptyDoubleClick(event) {
-    event.stopPropagation();
+  private onEmptyDoubleClick(event: Event) {
+    event.stopPropagation()
   }
 
-  updateNetworks() {
+  private updateNetworks() {
     this.browserProxy_.getNetworksList(this.coin).then(payload => {
       if (!payload) {
         return
@@ -242,42 +282,43 @@ class SettingsWalletNetworksList extends SettingsWalletNetworksListBase {
     })
   }
 
-  onAddNetworkDialogClosed_() {
+  private onAddNetworkDialogClosed_() {
     this.showAddWalletNetworkDialog_ = false
-    this.selectedNetwork = {}
+    this.selectedNetwork = null
     this.updateNetworks()
   }
 
-  onHideButtonClicked_(event) {
+  private onHideButtonClicked_(event: Event&{model: {item: NetworkInfo}}) {
     const chainId = event.model.item.chainId
-    if (this.hiddenNetworks.indexOf(event.model.item.chainId) > -1) {
-      this.browserProxy_.removeHiddenNetwork(chainId, this.coin).then((success) => {
-        this.updateNetworks()
-      })
+    if (this.hiddenNetworks.includes(event.model.item.chainId)) {
+      this.browserProxy_.
+        removeHiddenNetwork(chainId, this.coin).then((_success: boolean) => {
+          this.updateNetworks()
+        })
     } else {
-      this.browserProxy_.addHiddenNetwork(chainId, this.coin).then((success) => {
-        this.updateNetworks()
+      this.browserProxy_.
+        addHiddenNetwork(chainId, this.coin).then((_success: boolean) => {
+          this.updateNetworks()
       })
     }
   }
 
-  onNetworkMenuTapped_(event) {
+  private onNetworkMenuTapped_(event: Event&{model: {item: NetworkInfo}}) {
     this.selectedNetwork = event.model.item
     this.isDefaultNetwork =
       this.checkIsDefaultNetwork(this.selectedNetwork.chainId)
     this.canRemoveNetwork = this.canRemoveNetwork_(this.selectedNetwork)
     this.canResetNetwork = this.canResetNetwork_(this.selectedNetwork)
-    const actionMenu =
-        /** @type {!CrActionMenuElement} */ (this.$$('#network-menu').get());
-    actionMenu.showAt(event.target);
+    this.$$<CrLazyRenderElement<CrActionMenuElement>>('#network-menu')!.get()
+      .showAt(event.target as HTMLElement)
   }
 
-  onEditTap_() {
-    this.$$('cr-action-menu').close();
+  private onEditTap_() {
+    this.$$<CrActionMenuElement>('cr-action-menu')!.close()
     this.showAddWalletNetworkDialog_ = true
   }
 
-  onNetworkActionTapped_(event) {
+  private onNetworkActionTapped_(_event: Event) {
     this.showAddWalletNetworkDialog_ = true
   }
 }
diff --git a/browser/resources/settings/brave_wallet_page/wallet_networks_subpage.ts b/browser/resources/settings/brave_wallet_page/wallet_networks_subpage.ts
index 3a8206a85383..70b8954132b1 100644
--- a/browser/resources/settings/brave_wallet_page/wallet_networks_subpage.ts
+++ b/browser/resources/settings/brave_wallet_page/wallet_networks_subpage.ts
@@ -3,23 +3,25 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import 'chrome://resources/cr_elements/cr_button/cr_button.js'
+import './add_wallet_network_dialog.js'
+import './wallet_networks_list.js'
 
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
-import './add_wallet_network_dialog.js';
-import './wallet_networks_list.js';
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-
-import {BaseMixin} from '../base_mixin.js';
+import {BaseMixin} from '../base_mixin.js'
 
 import {getTemplate} from './wallet_networks_subpage.html.js'
 
-import {BraveWalletBrowserProxyImpl} from './brave_wallet_browser_proxy.js';
+import {
+  BraveWalletBrowserProxy,
+  BraveWalletBrowserProxyImpl
+} from './brave_wallet_browser_proxy.js'
 
-const SettingsWalletNetworksSubpageBase = PrefsMixin(I18nMixin(BaseMixin(PolymerElement)))
+const SettingsWalletNetworksSubpageBase =
+  PrefsMixin(I18nMixin(BaseMixin(PolymerElement)))
 
 class SettingsWalletNetworksSubpage extends SettingsWalletNetworksSubpageBase {
   static get is() {
@@ -63,18 +65,27 @@ class SettingsWalletNetworksSubpage extends SettingsWalletNetworksSubpageBase {
     }
   }
 
-  browserProxy_ = BraveWalletBrowserProxyImpl.getInstance()
+  private isZCashEnabled: boolean
+  private isBitcoinEnabled: boolean
+  private ethCoin: number
+  private filCoin: number
+  private solCoin: number
+  private btcCoin: number
+  private zecCoin: number
+
+  private browserProxy_: BraveWalletBrowserProxy =
+    BraveWalletBrowserProxyImpl.getInstance()
 
-  ready() {
+  override ready() {
     super.ready()
 
-    this.browserProxy_.isZCashEnabled().then(val => {
-      this.isZCashEnabled = val
-    });
+    this.browserProxy_.isZCashEnabled().then((enabled: boolean) => {
+      this.isZCashEnabled = enabled
+    })
 
-    this.browserProxy_.isBitcoinEnabled().then(val => {
-      this.isBitcoinEnabled = val
-    });
+    this.browserProxy_.isBitcoinEnabled().then((enabled: boolean) => {
+      this.isBitcoinEnabled = enabled
+    })
   }
 }
 
diff --git a/browser/resources/settings/default_brave_shields_page/brave_adblock_browser_proxy.ts b/browser/resources/settings/default_brave_shields_page/brave_adblock_browser_proxy.ts
index 79aaebdd47aa..7922cfe6234f 100644
--- a/browser/resources/settings/default_brave_shields_page/brave_adblock_browser_proxy.ts
+++ b/browser/resources/settings/default_brave_shields_page/brave_adblock_browser_proxy.ts
@@ -3,18 +3,38 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import { sendWithPromise, addWebUiListener } from 'chrome://resources/js/cr.js'
 
 export class Scriptlet {
   name: string
+
   kind: object = {
     mime: 'application/javascript'
   }
+
   content: string
 }
 
+export interface FilterList {
+  uuid: string
+  url: string
+  title: string
+  desc: string
+  support_url: string
+  component_id: string
+  base64_public_key: string
+  enabled: boolean
+}
+
+export interface SubscriptionInfo {
+  subscription_url: string
+  last_update_attempt: number
+  last_successful_update_attempt: number
+  enabled: boolean
+  title?: string
+  homepage?: string
+}
+
 export enum ErrorCode {
   kOK = 0,
   kInvalidName,
@@ -23,92 +43,75 @@ export enum ErrorCode {
 }
 
 export interface BraveAdblockBrowserProxy {
-  getRegionalLists(): Promise<any[]> // TODO(petemill): Define the expected type
-  enableFilterList(uuid: string, enabled: boolean)
-  updateFilterList(uuid: string): Promise<boolean>
-  getListSubscriptions(): Promise<any> // TODO(petemill): Define the expected type
-  getCustomFilters(): Promise<any> // TODO(petemill): Define the expected type
-  setSubscriptionEnabled(url: string, enabled: boolean)
-  addSubscription(url: string)
-  addWebUiListener(eventName: string, callback: Function)
-  updateSubscription(url: string)
-  deleteSubscription(url: string)
-  viewSubscription(url: string)
-  getCustomScriptlets(): Promise<Scriptlet[]>
-  addCustomScriptlet(scriptlet: Scriptlet): Promise<ErrorCode>
-  updateCustomScriptlet(name: string, scriptlet: Scriptlet): Promise<ErrorCode>
-  removeCustomScriptlet(name: string): Promise<ErrorCode>
+  getRegionalLists: () => Promise<FilterList[]>
+  enableFilterList: (uuid: string, enabled: boolean) => void
+  updateFilterLists: () => Promise<boolean>
+  getCustomFilters: () => Promise<string>
+  updateCustomFilters: (value: string) => void
+  getListSubscriptions: () => Promise<any>
+  setSubscriptionEnabled: (url: string, enabled: boolean) => void
+  addSubscription: (url: string) => void
+  updateSubscription: (url: string) => void
+  deleteSubscription: (url: string) => void
+  viewSubscription: (url: string) => void
+  getCustomScriptlets: () => Promise<Scriptlet[]>
+  addCustomScriptlet: (scriptlet: Scriptlet) => Promise<ErrorCode>
+  updateCustomScriptlet: (name: string, scriptlet: Scriptlet) =>
+    Promise<ErrorCode>
+  removeCustomScriptlet: (name: string) => Promise<ErrorCode>
+  addWebUiListener: (eventName: string, callback: Function) => void
 }
 
 export class BraveAdblockBrowserProxyImpl implements BraveAdblockBrowserProxy {
   static getInstance() {
-    return instance || (instance = new BraveAdblockBrowserProxyImpl());
+    return instance || (instance = new BraveAdblockBrowserProxyImpl())
   }
 
-  /** @returns {Promise} */
   getRegionalLists () {
     return sendWithPromise('brave_adblock.getRegionalLists')
   }
 
-  /** @returns {Promise} */
-  getListSubscriptions () {
-    return sendWithPromise('brave_adblock.getListSubscriptions')
+  enableFilterList (uuid: string, enabled: boolean) {
+    chrome.send('brave_adblock.enableFilterList', [uuid, enabled])
+  }
+
+  updateFilterLists () {
+    return sendWithPromise('brave_adblock.updateFilterLists')
   }
 
-  /** @returns {Promise} */
   getCustomFilters () {
     return sendWithPromise('brave_adblock.getCustomFilters')
   }
 
-  enableFilterList (uuid, enabled) {
-    chrome.send('brave_adblock.enableFilterList', [uuid, enabled])
+  updateCustomFilters (value: string) {
+    chrome.send('brave_adblock.updateCustomFilters', [value])
   }
 
-  /** @returns {Promise<boolean>} */
-  updateFilterLists () {
-    return sendWithPromise('brave_adblock.updateFilterLists')
+  getListSubscriptions () {
+    return sendWithPromise('brave_adblock.getListSubscriptions')
   }
 
-  setSubscriptionEnabled (url, enabled) {
+  setSubscriptionEnabled (url: string, enabled: boolean) {
     chrome.send('brave_adblock.setSubscriptionEnabled', [url, enabled])
   }
 
-  addSubscription (url) {
+  addSubscription (url: string) {
     chrome.send('brave_adblock.addSubscription', [url])
   }
 
-  updateSubscription (url) {
+  updateSubscription (url: string) {
     chrome.send('brave_adblock.updateSubscription', [url])
   }
 
-  updateCustomFilters (value) {
-    chrome.send('brave_adblock.updateCustomFilters', [value])
-  }
-
-  deleteSubscription (url) {
+  deleteSubscription (url: string) {
     chrome.send('brave_adblock.deleteSubscription', [url])
   }
 
-  viewSubscription (url) {
+  viewSubscription (url: string) {
     chrome.send('brave_adblock.viewSubscription', [url])
   }
 
-  utf8ToBase64_(str) {
-    const uint8Array = new TextEncoder().encode(str)
-    const base64String = btoa(String.fromCharCode.apply(null, uint8Array))
-    return base64String
-  }
-
-  base64ToUtf8_(base64) {
-    const binaryString = atob(base64)
-    const bytes = new Uint8Array(binaryString.length)
-    for (let i = 0; i < binaryString.length; i++) {
-      bytes[i] = binaryString.charCodeAt(i)
-    }
-    return new TextDecoder().decode(bytes)
-  }
-
-  getCustomScriptlets() {
+  getCustomScriptlets () {
     return sendWithPromise('brave_adblock.getCustomScriptlets')
       .then((scriptlets) => {
         for (const scriptlet of scriptlets) {
@@ -121,26 +124,39 @@ export class BraveAdblockBrowserProxyImpl implements BraveAdblockBrowserProxy {
       })
   }
 
-  addCustomScriptlet(scriptlet) {
+  addCustomScriptlet (scriptlet: Scriptlet) {
     scriptlet.content = this.utf8ToBase64_(scriptlet.content)
     return sendWithPromise('brave_adblock.addCustomScriptlet', scriptlet)
   }
 
-  updateCustomScriptlet(name, scriptlet) {
+  updateCustomScriptlet (name: string, scriptlet: Scriptlet) {
     scriptlet.content = this.utf8ToBase64_(scriptlet.content)
     return sendWithPromise(
-      'brave_adblock.updateCustomScriptlet',
-      name,
-      scriptlet
+      'brave_adblock.updateCustomScriptlet', name, scriptlet
     )
   }
 
-  removeCustomScriptlet(name) {
+  removeCustomScriptlet (name: string) {
     return sendWithPromise('brave_adblock.removeCustomScriptlet', name)
   }
 
-  addWebUiListener(event_name, callback) {
-    addWebUiListener(event_name, callback)
+  addWebUiListener (eventName: string, callback: Function) {
+    addWebUiListener(eventName, callback)
+  }
+
+  private utf8ToBase64_ (str: string) {
+    const uint8Array = new TextEncoder().encode(str)
+    const base64String = btoa(String.fromCharCode(...uint8Array))
+    return base64String
+  }
+
+  private base64ToUtf8_ (base64: string) {
+    const binaryString = atob(base64)
+    const bytes = new Uint8Array(binaryString.length)
+    for (let i = 0; i < binaryString.length; i++) {
+      bytes[i] = binaryString.charCodeAt(i)
+    }
+    return new TextDecoder().decode(bytes)
   }
 }
 
diff --git a/browser/resources/settings/default_brave_shields_page/brave_adblock_subpage.ts b/browser/resources/settings/default_brave_shields_page/brave_adblock_subpage.ts
index 001a79a52e49..4d5cae0581f5 100644
--- a/browser/resources/settings/default_brave_shields_page/brave_adblock_subpage.ts
+++ b/browser/resources/settings/default_brave_shields_page/brave_adblock_subpage.ts
@@ -3,26 +3,29 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import './components/brave_adblock_editor.js'
+import './components/brave_adblock_scriptlet_list.js'
+import './components/brave_adblock_subscribe_dropdown.js'
+
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {
+  type DomRepeatEvent,
+  PolymerElement
+} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
+
+import {BaseMixin} from '../base_mixin.js'
+
+import {
+  BraveAdblockBrowserProxy,
+  BraveAdblockBrowserProxyImpl,
+  FilterList,
+  SubscriptionInfo
+} from './brave_adblock_browser_proxy.js'
 
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
-import 'chrome://resources/cr_elements/icons.html.js';
-import './components/brave_adblock_subscribe_dropdown.js';
-import './components/brave_adblock_editor.js';
-import './components/brave_adblock_scriptlet_list.js';
-
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-
-import {BaseMixin} from '../base_mixin.js';
-
-import {BraveAdblockBrowserProxyImpl} from './brave_adblock_browser_proxy.js'
 import {getTemplate} from './brave_adblock_subpage.html.js'
 
-import { loadTimeData } from '../i18n_setup.js'
-
-import type {SettingsToggleButtonElement} from '../controls/settings_toggle_button.js';
+import {loadTimeData} from '../i18n_setup.js'
 
 const AdBlockSubpageBase = PrefsMixin(I18nMixin(BaseMixin(PolymerElement)))
 
@@ -55,9 +58,18 @@ class AdBlockSubpage extends AdBlockSubpageBase {
     }
   }
 
-  browserProxy_ = BraveAdblockBrowserProxyImpl.getInstance()
+  private filterList_: FilterList[]
+  private subscriptionList_: SubscriptionInfo[]
+  private customFilters_: string
+  private subscribeUrl_: string
+  private listsUpdatingState_: string
+  private hasListExpanded_: boolean
+  private cosmeticFilteringCustomScriptletsEnabled_: boolean
+
+  private browserProxy_: BraveAdblockBrowserProxy =
+    BraveAdblockBrowserProxyImpl.getInstance()
 
-  ready() {
+  override ready() {
     super.ready()
 
     this.listsUpdatingState_ = ''
@@ -75,18 +87,18 @@ class AdBlockSubpage extends AdBlockSubpageBase {
     })
 
     this.browserProxy_.addWebUiListener(
-      'brave_adblock.onGetListSubscriptions', (value) => {
+      'brave_adblock.onGetListSubscriptions', (value: SubscriptionInfo[]) => {
         this.subscriptionList_ = value
     })
   }
 
-  handleShowList_() {
+  private handleShowList_() {
     if (!this.hasListExpanded_) {
       this.hasListExpanded_ = true
     }
   }
 
-  handleUpdateLists_() {
+  private handleUpdateLists_() {
     if (this.listsUpdatingState_ === 'updating') {
       return
     }
@@ -100,72 +112,85 @@ class AdBlockSubpage extends AdBlockSubpageBase {
     })
   }
 
-  searchListBy_(title) {
+  private searchListBy_(title: string) {
     if (!title) {
       this.hasListExpanded_ = false
       return null
     }
 
-    return (item) => {
+    return (item: SubscriptionInfo) => {
       this.hasListExpanded_ = true
       title = title.toLowerCase()
-      return (item.title.toLowerCase().includes(title))
+      return (item.title?.toLowerCase().includes(title))
     }
   }
 
-  handleFilterListItemToggle_(e) {
-    this.browserProxy_.enableFilterList(e.model.get('item.uuid'), e.model.get('item.enabled'))
+  private handleFilterListItemToggle_(e: DomRepeatEvent<FilterList>) {
+    const filterList = e.model.item
+    this.browserProxy_.enableFilterList(filterList.uuid, filterList.enabled)
   }
 
-  handleSubscribeUrlItemItemToggle_(e) {
-    this.browserProxy_.setSubscriptionEnabled(e.model.get('item.subscription_url'), e.model.get('item.enabled'))
+  private handleSubscribeUrlItemItemToggle_(
+    e: DomRepeatEvent<SubscriptionInfo>)
+  {
+    const subscriptionInfo = e.model.item
+    this.browserProxy_.setSubscriptionEnabled(
+      subscriptionInfo.subscription_url, subscriptionInfo.enabled)
   }
 
-  onKeyUp_(e) {
+  private onKeyUp_(e: KeyboardEvent) {
     if (e.keyCode === 13) {
       this.handleSubmitUrl_()
     }
   }
 
-  handleSubmitUrl_() {
+  private handleSubmitUrl_() {
     const url = this.subscribeUrl_.trim()
     if (!url) return
 
     this.browserProxy_.addSubscription(url)
-    this.subscribeUrl_ = null
+    this.subscribeUrl_ = ''
   }
 
-  handleSave_(e) {
+  private handleSave_(e: CustomEvent) {
     const value = e.detail.value
     this.browserProxy_.updateCustomFilters(value)
   }
 
-  handleUpdateSubscription_(e) {
-    this.browserProxy_.updateSubscription(e.model.get('item.subscription_url'))
+  private handleUpdateSubscription_(
+    e: Event&{model: {item: SubscriptionInfo}})
+  {
+    this.browserProxy_.updateSubscription(e.model.item.subscription_url)
   }
 
-  handleDeleteSubscription_(e) {
-    this.browserProxy_.deleteSubscription(e.model.get('item.subscription_url'))
+  private handleDeleteSubscription_(
+    e: Event&{model: {item: SubscriptionInfo}})
+  {
+    this.browserProxy_.deleteSubscription(e.model.item.subscription_url)
   }
 
-  handleViewSubscription_(e) {
-    this.browserProxy_.viewSubscription(e.model.get('item.subscription_url'))
+  private handleViewSubscription_(
+    e: Event&{model: {item: SubscriptionInfo}})
+  {
+    this.browserProxy_.viewSubscription(e.model.item.subscription_url)
   }
 
-  getStringHtml_(id, link) {
+  private getStringHtml_(id: string, link: string) {
     return this.i18nAdvanced(id, { substitutions: [ link ]})
   }
 
-  isEqual_(lhs, rhs) {
+  private isEqual_(lhs: any, rhs: any) {
     return lhs === rhs
   }
 
-  isFailedUpdate_(item) {
-    return item.last_successful_update_attempt !== 0 && item.last_successful_update_attempt !== item.last_update_attempt
+  private isFailedUpdate_(item: SubscriptionInfo) {
+    return item.last_successful_update_attempt !== 0 &&
+           item.last_successful_update_attempt !== item.last_update_attempt
   }
 
-  isLastAttemptFailed_(item) {
-    return item.last_successful_update_attempt !== 0 && item.last_successful_update_attempt === item.last_update_attempt
+  private isLastAttemptFailed_(item: SubscriptionInfo) {
+    return item.last_successful_update_attempt !== 0 &&
+           item.last_successful_update_attempt === item.last_update_attempt
   }
 }
 
diff --git a/browser/resources/settings/default_brave_shields_page/components/brave_adblock_editor.ts b/browser/resources/settings/default_brave_shields_page/components/brave_adblock_editor.ts
index dfcf4cfcd2a9..5ad5039dc36d 100644
--- a/browser/resources/settings/default_brave_shields_page/components/brave_adblock_editor.ts
+++ b/browser/resources/settings/default_brave_shields_page/components/brave_adblock_editor.ts
@@ -3,15 +3,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import 'chrome://resources/cr_elements/cr_button/cr_button.js'
 
-import 'chrome://resources/cr_elements/cr_button/cr_button.js';
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-
-import {BaseMixin} from '../../base_mixin.js';
+import {BaseMixin} from '../../base_mixin.js'
 
 import {getTemplate} from './brave_adblock_editor.html.js'
 
@@ -29,17 +27,19 @@ class AdBlockFiltersEditor extends AdBlockFiltersEditorBase {
   static get properties() {
     return {
       value: {
-        type: Text
+        type: String
       }
     }
   }
 
-  ready() {
+  private value: string
+
+  override ready() {
     super.ready()
   }
 
-  handleInputChange_(e) {
-    this.value = e.target.value
+  handleInputChange_(e: Event) {
+    this.value = (e.target as HTMLInputElement).value
   }
 
   handleSave_() {
diff --git a/browser/resources/settings/default_brave_shields_page/components/brave_adblock_subscribe_dropdown.ts b/browser/resources/settings/default_brave_shields_page/components/brave_adblock_subscribe_dropdown.ts
index cdc9189015a1..9d980a2bbfee 100644
--- a/browser/resources/settings/default_brave_shields_page/components/brave_adblock_subscribe_dropdown.ts
+++ b/browser/resources/settings/default_brave_shields_page/components/brave_adblock_subscribe_dropdown.ts
@@ -3,21 +3,29 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import 'chrome://resources/cr_elements/cr_icon_button/cr_icon_button.js'
+import 'chrome://resources/cr_elements/icons.html.js'
 
-import 'chrome://resources/cr_elements/cr_action_menu/cr_action_menu.js';
-import 'chrome://resources/cr_elements/cr_icon_button/cr_icon_button.js';
-import 'chrome://resources/cr_elements/icons.html.js';
+import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
+import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
 
-import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js';
-import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js';
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-
-import {BaseMixin} from '../../base_mixin.js';
+import {BaseMixin} from '../../base_mixin.js'
 
 import {getTemplate} from './brave_adblock_subscribe_dropdown.html.js'
 
-const AdblockSubscribeDropDownBase = PrefsMixin(I18nMixin(BaseMixin(PolymerElement)))
+import type {
+  CrActionMenuElement
+} from 'chrome://resources/cr_elements/cr_action_menu/cr_action_menu.js'
+
+interface AdBlockSubscribeDropDown {
+  $: {
+    menu: CrActionMenuElement
+  }
+}
+
+const AdblockSubscribeDropDownBase =
+  PrefsMixin(I18nMixin(BaseMixin(PolymerElement)))
 
 class AdBlockSubscribeDropDown extends AdblockSubscribeDropDownBase {
   static get is() {
@@ -28,12 +36,8 @@ class AdBlockSubscribeDropDown extends AdblockSubscribeDropDownBase {
     return getTemplate()
   }
 
-  ready() {
-    super.ready()
-  }
-
-  handleDropdownClick_(e) {
-    this.$.menu.showAt(e.target)
+  handleDropdownClick_(e: Event) {
+    this.$.menu.showAt(e.target as HTMLElement)
   }
 
   updateSubscription_() {
diff --git a/browser/resources/settings/default_brave_shields_page/default_brave_shields_browser_proxy.ts b/browser/resources/settings/default_brave_shields_page/default_brave_shields_browser_proxy.ts
index 11d8c1438b37..3266b5ae49ee 100644
--- a/browser/resources/settings/default_brave_shields_page/default_brave_shields_browser_proxy.ts
+++ b/browser/resources/settings/default_brave_shields_page/default_brave_shields_browser_proxy.ts
@@ -6,175 +6,105 @@
 import {sendWithPromise} from 'chrome://resources/js/cr.js'
 
 export interface DefaultBraveShieldsBrowserProxy {
-  /**
-   * @return {!Promise<boolean>}
-   */
-  isAdControlEnabled(): Promise<boolean>
-  /**
-   * @param {string} value name.
-   */
-  setAdControlType(value: string): void
-
-  /**
-   * @return {!Promise<boolean>}
-   */
-  isFirstPartyCosmeticFilteringEnabled(): Promise<boolean>
-  /**
-   * @param {string} value name.
-   */
-  setCosmeticFilteringControlType(value: string): void
-
-  /**
-   * @return {!Promise<string>}
-   */
-  getCookieControlType(): Promise<string>
-  /**
-   * @param {string} value name.
-   */
-  setCookieControlType(value: string): void
-
-  /**
-   * @return {!Promise<string>}
-   */
-  getFingerprintingControlType(): Promise<string>
-  /**
-   * @param {string} value name.
-   */
-  setFingerprintingControlType(value: string): void
-
-  /**
-   * @return {!Promise<boolean>}
-   */
-  getFingerprintingBlockEnabled(): Promise<boolean>
-  /**
-   * @param {boolean} value name.
-   */
-  setFingerprintingBlockEnabled(value: boolean): void
-
-  /**
-   * @return {!Promise<string>}
-   */
-  getHttpsUpgradeControlType(): Promise<string>
-  /**
-   * @param {string} value name.
-   */
-  setHttpsUpgradeControlType(value: string): void
-
-  /**
-   * @param {string} value name.
-   */
-  setNoScriptControlType(value: string): void
-
-  /**
-   * @return {!Promise<boolean>}
-   */
-  getForgetFirstPartyStorageEnabled(): Promise<boolean>
-  /**
-   * @param {Boolean} value name.
-   */
-  setForgetFirstPartyStorageEnabled(value: boolean): void
-
-  /**
-   * @param {string} value name.
-   */
-  setContactInfoSaveFlag(value: boolean): void
-  /**
-   * @return {!Promise<boolean>}
-   */
-  getContactInfoSaveFlag(): Promise<boolean>
-  /**
-   * @return {!Promise<boolean>}
-   */
-  getHideBlockAllCookieTogle(): Promise<boolean>
+  isAdControlEnabled: () => Promise<boolean>
+  setAdControlType: (value: boolean) => void
+
+  isFirstPartyCosmeticFilteringEnabled: () => Promise<boolean>
+  setCosmeticFilteringControlType: (value: string) => void
+
+  getCookieControlType: () => Promise<string>
+  setCookieControlType: (value: string) => void
+
+  getFingerprintingControlType: () => Promise<string>
+  setFingerprintingControlType: (value: string) => void
+
+  getFingerprintingBlockEnabled: () => Promise<boolean>
+  setFingerprintingBlockEnabled: (value: boolean) => void
+
+  getHttpsUpgradeControlType: () => Promise<string>
+  setHttpsUpgradeControlType: (value: string) => void
+
+  setNoScriptControlType: (value: boolean) => void
+
+  getForgetFirstPartyStorageEnabled: () => Promise<boolean>
+  setForgetFirstPartyStorageEnabled: (value: boolean) => void
+
+  setContactInfoSaveFlag: (value: boolean) => void
+  getContactInfoSaveFlag: () => Promise<boolean>
+
+  getHideBlockAllCookieTogle: () => Promise<boolean>
 }
 
-export class DefaultBraveShieldsBrowserProxyImpl implements DefaultBraveShieldsBrowserProxy {
-  /** @override */
+export class DefaultBraveShieldsBrowserProxyImpl
+implements DefaultBraveShieldsBrowserProxy {
   isAdControlEnabled () {
     return sendWithPromise('isAdControlEnabled')
   }
 
-  /** @override */
-  setAdControlType (value: string) {
+  setAdControlType (value: boolean) {
     chrome.send('setAdControlType', [value])
   }
 
-  /** @override */
   isFirstPartyCosmeticFilteringEnabled () {
     return sendWithPromise('isFirstPartyCosmeticFilteringEnabled')
   }
 
-  /** @override */
   setCosmeticFilteringControlType (value: string) {
     chrome.send('setCosmeticFilteringControlType', [value])
   }
 
-  /** @override */
   getCookieControlType () {
-    return sendWithPromise('getCookieControlType');
+    return sendWithPromise('getCookieControlType')
   }
 
-  /** @override */
   setCookieControlType (value: string) {
-    chrome.send('setCookieControlType', [value]);
+    chrome.send('setCookieControlType', [value])
   }
 
-  /** @override */
   getFingerprintingControlType () {
-    return sendWithPromise('getFingerprintingControlType');
+    return sendWithPromise('getFingerprintingControlType')
   }
 
-  /** @override */
   setFingerprintingControlType (value: string) {
     chrome.send('setFingerprintingControlType', [value])
   }
 
-  /** @override */
   getFingerprintingBlockEnabled () {
     return sendWithPromise('getFingerprintingBlockEnabled')
   }
 
-  /** @override */
   setFingerprintingBlockEnabled (value: boolean) {
     chrome.send('setFingerprintingBlockEnabled', [value])
   }
 
-  /** @override */
   getHttpsUpgradeControlType () {
     return sendWithPromise('getHttpsUpgradeControlType')
   }
 
-  /** @override */
   setHttpsUpgradeControlType (value: string) {
     chrome.send('setHttpsUpgradeControlType', [value])
   }
 
-  /** @override */
-  setNoScriptControlType (value: string) {
+  setNoScriptControlType (value: boolean) {
     chrome.send('setNoScriptControlType', [value])
   }
 
-  /** @override */
   getForgetFirstPartyStorageEnabled () {
     return sendWithPromise('getForgetFirstPartyStorageEnabled')
   }
 
-  /** @override */
   setForgetFirstPartyStorageEnabled (value: boolean) {
     chrome.send('setForgetFirstPartyStorageEnabled', [value])
   }
 
-  /** @override */
   setContactInfoSaveFlag (value: boolean) {
     chrome.send('setContactInfoSaveFlag', [value])
   }
 
-  /** @override */
   getContactInfoSaveFlag () {
     return sendWithPromise('getContactInfoSaveFlag')
   }
 
-  /** @override */
   getHideBlockAllCookieTogle () {
     return sendWithPromise('getHideBlockAllCookieTogle')
   }
diff --git a/browser/resources/settings/default_brave_shields_page/default_brave_shields_page.ts b/browser/resources/settings/default_brave_shields_page/default_brave_shields_page.ts
index 4b455a1ac9e6..2418db08b8ec 100644
--- a/browser/resources/settings/default_brave_shields_page/default_brave_shields_page.ts
+++ b/browser/resources/settings/default_brave_shields_page/default_brave_shields_page.ts
@@ -3,8 +3,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import './brave_adblock_subpage.js'
 import '//resources/cr_elements/md_select.css.js'
 
@@ -12,17 +10,38 @@ import {PolymerElement} from '//resources/polymer/v3_0/polymer/polymer_bundled.m
 import {PrefsMixin} from '/shared/settings/prefs/prefs_mixin.js'
 import {I18nMixin} from 'chrome://resources/cr_elements/i18n_mixin.js'
 import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js'
-import {assertNotReached} from 'chrome://resources/js/assert.js'
 
 import {loadTimeData} from '../i18n_setup.js'
 import {RouteObserverMixin, Router} from '../router.js'
-import {routes} from '../route.js'
-import {CookieControlsMode} from '../site_settings/constants.js'
+import {SettingsToggleButtonElement} from '../controls/settings_toggle_button.js'
+
+import {
+  DefaultBraveShieldsBrowserProxy,
+  DefaultBraveShieldsBrowserProxyImpl
+} from './default_brave_shields_browser_proxy.js'
 
-import {DefaultBraveShieldsBrowserProxyImpl, DefaultBraveShieldsBrowserProxyImpl} from './default_brave_shields_browser_proxy.js'
 import {getTemplate} from './default_brave_shields_page.html.js'
 
-const BraveShieldsPageBase = WebUiListenerMixin(I18nMixin(PrefsMixin(RouteObserverMixin(PolymerElement))))
+interface BraveShieldsPage {
+  $: {
+    adControlType: HTMLSelectElement,
+    cookieControlType: HTMLSelectElement,
+    fingerprintingToggleControlType: SettingsToggleButtonElement,
+    fingerprintingSelectControlType: HTMLSelectElement,
+    forgetFirstPartyStorageControlType: SettingsToggleButtonElement,
+    httpsUpgradeControlType: HTMLSelectElement,
+    noScriptControlType: SettingsToggleButtonElement,
+    setContactInfoSaveFlagToggle: SettingsToggleButtonElement,
+  }
+}
+
+type ControlType = {
+  name: string
+  value: string
+}
+
+const BraveShieldsPageBase =
+  WebUiListenerMixin(I18nMixin(PrefsMixin(RouteObserverMixin(PolymerElement))))
 
 /**
  * 'settings-default-brave-shields-page' is the settings page containing brave's
@@ -141,7 +160,22 @@ class BraveShieldsPage extends BraveShieldsPageBase {
     }
   }
 
-  browserProxy_ = DefaultBraveShieldsBrowserProxyImpl.getInstance()
+  private adControlTypes_: ControlType[]
+  private adControlType_: 'allow' | 'block' | 'block_third_party'
+  private isAdBlockRoute_: boolean
+  private cookieControlTypes_: ControlType[]
+  private cookieControlType_: string
+  private httpsUpgradeControlType_: string
+  private isForgetFirstPartyStorageEnabled_: chrome.settingsPrivate.
+    PrefObject<boolean>
+  private isFingerprintingEnabled_: chrome.settingsPrivate.PrefObject<boolean>
+  private isContactInfoSaveFlagEnabled_: chrome.settingsPrivate.
+    PrefObject<boolean>
+  private fingerprintingControlTypes_: ControlType[]
+  private fingerprintingControlType_: string
+
+  private browserProxy_: DefaultBraveShieldsBrowserProxy =
+    DefaultBraveShieldsBrowserProxyImpl.getInstance()
 
   override ready () {
     super.ready()
@@ -152,10 +186,10 @@ class BraveShieldsPage extends BraveShieldsPageBase {
       () => { this.onShieldsSettingsChanged_() })
   }
 
-  /** @protected */
   override currentRouteChanged () {
     const router = Router.getInstance()
-    this.isAdBlockRoute_ = (router.getCurrentRoute() == router.getRoutes().SHIELDS_ADBLOCK)
+    this.isAdBlockRoute_ =
+      (router.getCurrentRoute() === router.getRoutes().SHIELDS_ADBLOCK)
   }
 
   onAdblockPageClick_() {
@@ -163,18 +197,19 @@ class BraveShieldsPage extends BraveShieldsPageBase {
     router.navigateTo(router.getRoutes().SHIELDS_ADBLOCK)
   }
 
-  controlEqual_ (val1, val2) {
+  controlEqual_ (val1: any, val2: any) {
     return val1 === val2
   }
 
   onShieldsSettingsChanged_ () {
-    Promise.all([this.browserProxy_.isAdControlEnabled(), this.browserProxy_.isFirstPartyCosmeticFilteringEnabled()])
-      .then(([adControlEnabled, hide1pContent]) => {
+    Promise.all([
+      this.browserProxy_.isAdControlEnabled(),
+      this.browserProxy_.isFirstPartyCosmeticFilteringEnabled()
+    ]).then(([adControlEnabled, hide1pContent]) => {
       if (adControlEnabled) {
-          this.adControlType_ = hide1pContent ? 'block' : 'block_third_party'
-      }
-      else {
-          this.adControlType_ = 'allow'
+        this.adControlType_ = hide1pContent ? 'block' : 'block_third_party'
+      } else {
+        this.adControlType_ = 'allow'
       }
     })
 
@@ -202,7 +237,7 @@ class BraveShieldsPage extends BraveShieldsPageBase {
       this.isFingerprintingEnabled_ = {
         key: '',
         type: chrome.settingsPrivate.PrefType.BOOLEAN,
-        value: value != 'allow',
+        value: value !== 'allow',
       }
     })
 
diff --git a/browser/resources/settings/pin_shortcut_page/pin_shortcut_page.ts b/browser/resources/settings/pin_shortcut_page/pin_shortcut_page.ts
index 6673cfe10fe1..a03a23460b1f 100644
--- a/browser/resources/settings/pin_shortcut_page/pin_shortcut_page.ts
+++ b/browser/resources/settings/pin_shortcut_page/pin_shortcut_page.ts
@@ -1,16 +1,14 @@
 /* Copyright (c) 2022 The Brave Authors. All rights reserved.
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * you can obtain one at https://mozilla.org/MPL/2.0/. */
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
+import '../settings_shared.css.js'
+import '../settings_vars.css.js'
 
-import '../settings_shared.css.js';
-import '../settings_vars.css.js';
-
-import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
-import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js';
-import {SettingsPinShortcutPageBrowserProxyImpl} from './pin_shortcut_page_browser_proxy.js';
+import {PolymerElement} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js'
+import {WebUiListenerMixin} from 'chrome://resources/cr_elements/web_ui_listener_mixin.js'
+import {SettingsPinShortcutPageBrowserProxyImpl} from './pin_shortcut_page_browser_proxy.js'
 import {getTemplate} from './pin_shortcut_page.html.js'
 
 const SettingsPinShortcutPageBase = WebUiListenerMixin(PolymerElement)
@@ -33,15 +31,18 @@ class SettingsPinShortcutPage extends SettingsPinShortcutPageBase {
     }
   }
 
-  browserProxy_ = SettingsPinShortcutPageBrowserProxyImpl.getInstance()
+  private pinned_: boolean
+
+  private browserProxy_: SettingsPinShortcutPageBrowserProxyImpl =
+    SettingsPinShortcutPageBrowserProxyImpl.getInstance()
 
-  ready() {
+  override ready() {
     super.ready()
     this.pinned_ = false
 
     this.browserProxy_.checkShortcutPinState()
-    this.addWebUiListener(
-      'shortcut-pin-state-changed', pinned => this.set('pinned_', pinned))
+    this.addWebUiListener('shortcut-pin-state-changed',
+      (pinned: boolean) => this.set('pinned_', pinned))
   }
 
   onPinShortcutTap_() {
diff --git a/ui/webui/resources/cr_components/certificate_manager/brave_overrides/certificate_manager_v2.ts b/ui/webui/resources/cr_components/certificate_manager/brave_overrides/certificate_manager_v2.ts
index a612c43f9e0f..b537e7ff0b29 100644
--- a/ui/webui/resources/cr_components/certificate_manager/brave_overrides/certificate_manager_v2.ts
+++ b/ui/webui/resources/cr_components/certificate_manager/brave_overrides/certificate_manager_v2.ts
@@ -3,8 +3,6 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this file,
 // You can obtain one at https://mozilla.org/MPL/2.0/.
 
-// @ts-nocheck TODO(petemill): Define types and remove ts-nocheck
-
 import {RegisterStyleOverride} from '//resources/brave/polymer_overriding.js'
 import {html} from '//resources/polymer/v3_0/polymer/polymer_bundled.min.js'