When a textbox element is disabled in the content area under Chrome and Edge Chromium, the editor loses cursor and its toolbar/commands stop working.

Steps to repro:

1. Set the following content in HTML mode:
   

   test <textarea disabled="disabled">Text Box</textarea> test

2. Switch to Design mode
3. Click on the textbox
4. Click outside the textbox and you'll see that the cursor (selection) is missing
5. the majority of the toolbar features that rely on selection also do not work