Subject: Re: bug#74523: 31.0.50; `apply` elements screw up undo in region

From: Stefan Monnier <[email-masked]>
Date: Mon, 25 Nov 2024 10:19:36 -0500

> We currently don't support `apply` undo-elements very well (if at all)
> in the undo-in-region feature.
> Those elements used to be rare, but now that `comment-region` and other
> users of `combine-change-calls` generate them, it's not as rare.

I pushed a patch which fixes the test I sent, but `apply` elements are
still never included in undo-in-region.

Fixing that won't be easy in general: we have no way for
`undo-adjust-elt` to handle them correctly.

        Stefan