Disable spell check for Chromium 96 based browsers by default to work around editor performance issue

Issue Summary

A change was introduced in Chromium 96 that resulted in a performance regression when the browser's native spell check was used. This affected all Chromium 96 based browsers e.g. Chrome 96 and Edge 96.

As some enterprises may be stuck on Chrome 96 for some time before they are able to upgrade, we propose shipping a workaround inside Confluence that automatically disables spell check for affected browsers.

Steps to Reproduce

1. Edit/create a page or comment in Chrome 96 / Edge 96
2. Ensure spell check is enabled
3. Try scrolling or making changes to the document

Expected Results

The editor is responsive and changes are reflected on the screen quickly

Actual Results

The editor is not responsive and changes take time to reflect on the screen

Workaround

Any one of these can be done to mitigate the issue:

• Upgrade to Chromium 97 based browser (recommended option)
• Turn off the built in spell check feature
• Use a non-Chromium based browser e.g. Firefox
• Downgrade to Chromium 95 based browser