Tinymce error on resize window

What is the current behavior? When tinymce is loaded as disabled then resize window and enable editor a strange error occur

steps to reproduce link: https://5oi3i.csb.app/

1. load in small size 900 for example
2. resize window to 1200
3. press toggle
4. press toggle

source code: https://codesandbox.io/s/tinymcereact-5oi3i?file=/src/index.js:0-1646

The component must be in a context to send: getByDom
<div aria-pressed="false" aria-label="Bullet list" title="Bullet list" role="button" aria-haspopup="true" unselectable="on" tabindex="-1" class="tox-split-button tox-tbtn--disabled" style="user-select: none;" aria-disabled="true" aria-expanded="false" aria-describedby="aria_2622540402021592495008207"></div> is not in context

What is the expected behavior? Editor should permit enable/disable edit mode without errors

Which versions of TinyMCE, and which browser / OS are affected by this issue? Did this work in previous versions of TinyMCE or tinymce-react?

• TinyMCE react 3.6.0 same behavior on 3.5.0 not tested in more previous
• Ubuntu 20.04 Chrome 81.0.4044.122 and Firefox

[tiny-james]

I have replicated this in pure TinyMCE here: http://fiddle.tinymce.com/Vrhaab/2

An expert in TinyMCE’s UI library looked into it and came up with this explanation:

• the editor is resized via css. Nothing happens immediately.
• the setMode(‘design’) is called. This ends with a nodeChange.
• the components listening to the nodeChange are identified by EventDispatcher. This includes the components that are about to be removed from the DOM because they no longer fit in the smaller toolbar
• iframe’s nodeChange listener fires, which calls resizeContent
• iframe’s resizeContent handler fires which calls refresh on the toolbar, and removes all the toolbar groups that don’t fit in the new editor width. This also removes the nodeChange handlers from these components
• the current nodeChange event keeps iterating through all the listeners identified up-front. Finds the toolbar buttons that were just removed. Tries to call their handlers and an error occurs.

There is now a ticket in the TinyMCE backlog to fix this issue with this explanation and a suggested fix. When that gets completed I will update this issue.

[tiny-james]

This fix is now likely to be in TinyMCE 5.8 (it did not make 5.7).