Explore seamless termination of layout shift in editor

[westonruter]

As noted in the readme, layout shift termination only happens manually for each blog inserted:

Screen.recording.2023-02-27.13.57.01.webm

While this button is great for development purposes, a user shouldn't need to know to push such a button. Ideally this process would happen in the background whenever an embed block is added or modified. While the layout termination is happening, the Publish/Update button should be disabled.

Alternatively, there could be a pre-publish panel for eliminating layout shift, but that wouldn't work for updates.

[thelovekesh]

It's the next task on my list. Will work on making it seamless.

Also, will try to use the iframe's sandbox attribute, as it's available on major browsers now.