Using ts-ignore to avoid escaping expando properties.

1. Switched to using // @ts-ignore in code. This turns off type checking for that line of code.
2. Using this to avoid having to write element['mounted'].
3. Alternative:
// @ts-ignore
element.mounted

lib/mount.js

@@ -20,7 +20,8 @@ export const mount = (tag, container, elementToHydrate) => {
   if (tag.props && tag.props.onComponentDidMount) {
     tag.props.onComponentDidMount.call(tag.props.onComponentDidMount, element)
   }
-  element['mounted'] = true
+  // @ts-ignore
+  element.mounted = true
   if (elementToHydrate) {
     if (typeof elementToHydrate === 'string') {
       elementToHydrate = document.querySelector(elementToHydrate)

lib/patch.js

@@ -8,12 +8,13 @@ import { patchElement } from './utils/patchElement'
  */
 export function patch(node, element) {
   if (element) {
-    patchElement(element.parentNode, element, element && element['vnode'], node)
+    // @ts-ignore
+    patchElement(element.parentNode, element, element && element.vnode, node)
   } else {
     element = patchElement(null, null, null, node)
   }
-
-  element['vnode'] = node
+  // @ts-ignore
+  element.vnode = node
 
   return element
 }

lib/utils/patchElementHelpers/removeChildren.js

@@ -1,15 +1,14 @@
 /**
  * @description A function to remove the children of a node.
  * @param {Node} element The parent of the node whose children will be removed.
- * @namespace {Node} node The node whose children will be removed.
- * @property {Object} node.props
+ * @param {Node} node The node whose children will be removed.
  * @returns {Node} element The parent of the removed nodes.
  */
 export function removeChildren(element, node) {
-  const props = node.props
+  const props = node['props']
   if (props) {
-    for (let i = 0; i < node.children.length; i++) {
-      removeChildren(element.childNodes[i], node.children[i])
+    for (let i = 0; i < /** @type {Element} */ (node).children.length; i++) {
+      removeChildren(element.childNodes[i], /** @type {Element} */ (node).children[i])
     }
   }
   return element

lib/utils/patchElementHelpers/updateElement.js

@@ -19,8 +19,9 @@ export function updateElement(element, oldProps, props, isSVG) {
       setProp(element, prop, props[prop], oldProps[prop], isSVG)
     }
   }
+  // @ts-ignore
   // Handle lifecycle hook:
-  if (element['mounted'] && props && props.onComponentDidUpdate) {
+  if (element.mounted && props && props.onComponentDidUpdate) {
     props.onComponentDidUpdate.call(
       props.onComponentDidUpdate,
       oldProps,

package.json

@@ -1,6 +1,6 @@
 {
   "name": "composi",
-  "version": "2.4.8",
+  "version": "2.4.9",
   "description": "A JavaScript library for creating websites, PWAs and hybrid apps.",
   "main": "index.js",
   "scripts": {