martin rudalics <rudalics@gmx.at> writes:

>> Please push it for me.
>
> Pushed now.  Please have a look.

(For context: this was commit 8232325337 "Handle case where a face's
:extend attribute is unspecified (Bug#37774)".)

I think there might have been a regression since this commit: in-between
1c29ba0340 (2019-11-17) and 21790e5473 (2019-12-05), something caused
the backgrounds to no longer extend for faces with unspecified :extend
inheriting faces with :extend t.

The attached theme sets :extend t for diff-{added,removed}, and sets
:inherit (diff-…) for ediff-fine-diff-{A,B}.