Created attachment 272860 [details] [review]
Fix W32 theme for spinbuttons

It seems that the dec-button no longer has a "bottom" selector-thingy to
select for. Use "last-child" instead.

Created attachment 272861 [details]
How it looks without the patch

Created attachment 272862 [details]
How it looks with the patch

Review of attachment 272860 [details] [review]:

in principle it looks good, but I wonder if you tested with right-to-left locales, and see if it still matches, or we need to add a `dir(rtl)` selector.

Ah, actually, it doesn't work. It works for horizontally-oriented spinbuttons, but buttons meaning is reversed for vertically-oriented ones. And i haven't got a clue about RTL.

Created attachment 272864 [details] [review]
Fix W32 theme for spinbuttons (v2)

It seems that the dec-button no longer has a "bottom" selector-thingy to
select for. Use "last-child" instead.
Use .vertical to style vertical instance differently, as last-child/first-child
meaning is inverted there.
Increase (towards 0) margins a bit, to avoid clipping the pre-light rectangle.

Yep, it doesn't work with RTL.

Actually, vertical ones, which i've just fixed up, do work with RTL, since RTL doesn't change anything for them - "inc" is always first-child, "dec" is always last-child, entry is in the middle.
for horizontal ones, "last-child" is, apparently, the entry, so both buttons are styled as "dec".

Created attachment 272865 [details] [review]
Fix W32 theme for spinbuttons (v3)

It seems that the dec-button no longer has a "bottom" selector-thingy to
select for. Use "last-child" instead.
Use .vertical to style vertical instance differently, as last-child/first-child
meaning is inverted there.
Increase (towards 0) margins a bit, to avoid clipping the pre-light rectangle.
Use dir(rtl) selector to style horizontal instance differently for RTL locales,
where first-child is "inc".

Attachment 272865 [details] pushed as ce9437d - Fix W32 theme for spinbuttons