Making it possible to associate the EditContext with multiple Elements

The rich text editor applications often nests the contenteditable false and true elements to each other.

<div class="root-editable" contenteditable="true">
  editable text
  <div class="nested-context" contenteditable="false">
    <div class="nested-editable" contenteditable="true">
       nested editable text
     </div>
  </div>
</div>

Contenteditable

With the contenteditable element, we can add an event listener to the element that will propagate through all of its descendants, which makes possible for the nested-editable to use the same functionality that was written for the root-editable.
E.g.:

const rootEditable = document.querySelector('.root-editable");
rootEditable.addEventListener("keydown", (e) => {
 // Event fires if the focus was in either the RootEditable or the NestedEditable
});

EditContext

In case of the EditContext, the event listener is attached to its instance that currently prevents to apply the functionality for multiple elements.

const rootEditable = document.querySelector('.root-editable");
const editContext = new EditContext();
rootEditable.editContext = editContext;

editContext.ontextupdate = (event) => {
  // Event fires only if the focus was on the RootEditable (it doesnt fire  if the focus is on the NestedEditable)
}

Solution

If we would be able to apply the EditContext's instance to multiple elements, that would solve this issue.

The issue provides nested contenteditable examples and describes the EditContext event behavior, but names no repository files, tests, or entry points. Start by locating the EditContext specification or implementation area, then examine how an instance is associated with an element. Done means one EditContext can support the multiple nested editable elements described in the issue.