This seems to work well for me. It does expose a little bit of weirdness, for example, ctrl-F selects all of the text when the search button is already focused. However, that's a lot less weirdness than the way it is now.

It does seem natural for ui_do_but_textedit to return its return value anyway.

I would like either @Julian Eisel (Severin) or @Campbell Barton (campbellbarton) to look at this though, they would have a much better idea of whether there is a good reason not to do this.

Thanks for checking this out.

In my opinion, selecting all the text in the search box, on starting a new search by Ctrl+F is a desirable behavior. It's much quicker than having to delete the previous text first, when trying a new search term. Though I didn't plan for this.

In general it's unclear what the effects are of making this non-blocking. You can delete objects, open a file browser, insert keyframes, split the editor, etc.

It may be that those things work fine, but this needs some stress testing to find out what happens in such corner cases.

I was skeptical too and checked out the patch a bit ago - it seemed reliable, but I only really played with it for a minute. Indeed what troubles me is that it's hard to estimate consequences and possible corner cases. It's removing an isolation that was there since a very long time, code was built around it.
Might also be a good idea to do some testing with the Preferences → Experimental → Legacy Undo enabled, since the new undo does as little work as possible and thus tends to disguise some issues (while still having its own ones).

That said, if this can be made to work well, it's a great and welcome improvement.

@Brecht Van Lommel (brecht) Agreed. And my current plan is to pass through only the events we are interested to pass through (WHEELDOWNMOUSE, WHEELUPMOUSE, MIDDLEMOUSE, maybe something else like zoom, etc.). For that I intend to leave everything as is in this patch, but modify ui_do_but_textedit so it blocks everything except those events. Currently it passes through every event it doesn't handle. Though I need a bit more time to play with this to check if I'm not missing something.