diff --git a/__tests__/state.test.js b/__tests__/state.test.js
new file mode 100644
index 0000000..2e516bb
--- /dev/null
+++ b/__tests__/state.test.js
@@ -0,0 +1,170 @@
+window.webStorageObject = require('../src/assets/js/web-storage-object')
+
+const tabs = [
+    {
+        id: 1
+    },
+    {
+        id: 2
+    },
+    {
+        id: 3
+    }
+]
+
+const createBrowser = () => {
+    browser = {
+        runtime: {
+            onMessage: {
+                addListener(listener) {
+                    this.listener = listener
+                }
+            },
+            onMessageExternal: {
+                addListener(listener) {
+                    this.listener = listener
+                }
+            },
+            getManifest() {
+                return {
+                    version: 2
+                }
+            }
+        },
+        tabs: {
+            sendMessage() {},
+            query(options, callback) {
+                if (options.active && options.currentWindow) {
+                    callback([tabs[0]])
+                }
+
+                callback([...tabs])
+            },
+        },
+        browserAction: {
+            setIcon() {},
+            onClicked: {
+                addListener(listener) {
+                    this.listener = listener
+                }
+            }
+        }
+    }
+}
+
+const dictionary = {
+    localhost: 'It works! Good job!',
+    twitter: 'Tweets can only be 280 characters long!',
+    github: 'Need lessons in Python?',
+    quora: [
+        '????????????????',
+        'What is my purpose?'
+    ]
+}
+
+beforeEach(() => {
+    createBrowser()
+    require('../src/assets/js/state')
+})
+
+afterEach(() => {
+    jest.resetModules();
+})
+
+test('isActive listener', () => {
+    expect.assertions(2)
+
+    browser.runtime.onMessage.listener({ name: 'isActive' }, {}, (response) => {
+        expect(response).toEqual({
+            name: 'isActive',
+            value: true
+        })
+    })
+
+    window.settings.isActive = false
+
+    browser.runtime.onMessage.listener({ name: 'isActive' }, {}, (response) => {
+        expect(response).toEqual({
+            name: 'isActive',
+            value: false
+        })
+    })
+})
+
+test('comments listener', () => {
+    function XMLHttpRequest() {
+        return {
+            send() {
+                if (typeof this.onreadystatechange() === 'function') {
+                    this.onreadystatechange()
+                }
+            },
+            open() {
+                this.readyState = 4
+                this.status = 200
+                this.response = JSON.stringify(dictionary)
+            }
+        }
+    }
+    global.XMLHttpRequest = XMLHttpRequest
+
+    browser.runtime.onMessage.listener({ name: 'comments' })
+
+    expect(window.settings.comments).toEqual(dictionary)
+})
+
+test('idle listener', () => {
+    expect.assertions(4)
+    jest.useFakeTimers()
+    let lastId
+    let lastMessage
+    browser.tabs.sendMessage = (id, message) => {
+        if (message.name === 'animate') {
+            lastId = id
+            lastMessage = message
+        }
+    }
+
+    window.settings.isActive = false
+    browser.runtime.onMessage.listener({ name: 'idle' })
+    jest.runAllTimers()
+
+    expect(lastId).toBeUndefined()
+    expect(lastMessage).toBeUndefined()
+
+    window.settings.isActive = true
+    browser.runtime.onMessage.listener({ name: 'idle' })
+    jest.runAllTimers()
+
+    expect(lastId).toEqual(1)
+    expect(lastMessage).toEqual({
+        name: 'animate',
+        value: true
+    })
+})
+
+it('should toggle button icons on click', () => {
+    expect.assertions(tabs.length * 2)
+
+    browser.browserAction.setIcon = (payload) => {
+        expect(payload.path).toBeDefined()
+        expect(payload.tabId).toBeDefined()
+    }
+
+    browser.browserAction.onClicked.listener()
+})
+
+it('should toggle isActive status on click', () => {
+    expect.assertions(tabs.length * 2)
+    window.settings.isActive = true
+
+    browser.tabs.sendMessage = (tabId, message) => {
+        expect(tabId).toBeDefined()
+        expect(message).toEqual({
+            name: 'isActive',
+            value: false
+        })
+    }
+
+    browser.browserAction.onClicked.listener()
+})
diff --git a/src/assets/js/state.js b/src/assets/js/state.js
index b5f6378..7be4867 100644
--- a/src/assets/js/state.js
+++ b/src/assets/js/state.js
@@ -143,3 +143,5 @@ browser.runtime.onMessageExternal.addListener((request, sender, sendResponse) =>
 
     return true
 })
+
+window.settings = settings