Ella

Thank you for the PR! Looks good, just left some comments.

Yes, I'll add a test, and I'll lock the function as a private api for now

I've considered this before and we were worries about false positives, but maybe that worry is questionable. Input rules can be undone with cmd+z, Backspace, and Escape I believe.

I'm not sure about this. It's a solution that imo makes both experiences a bit worse. You no longer have a full view of the content, and neither do you...

What we could do is combine both approaches. So have a toggle in the header (the one from [Move legacy meta boxes to toggle](https://github.com/WordPress/gutenberg/pull/59242)), and also the resizing. So by...

> Currently, the header component is integrated into the editor package. Is it possible to display the meta box toggle only in the post editor? It can probably be an...

This is wonderful! Can we keep the details toggle for any screen size? I think we need a way to quickly show and hide at all times. Not sure if...

> If considered necessary I think a toggle is necessary, imo. Like I said before, this can be in the form of a top toolbar button. I think that's actually...

You can actually keep everything as it is now, and just add the toggle to the top toolbar to add/remove the whole thing. The details is probably still useful for...

> Though, if I understand correctly just persisting the toggled and resized state meets minimum viability to land? It would be nice, but can also be polish later. Feel free...