1985558 - changing scrollbar colors for sidebar via userChrome.css no longer works

Status: RESOLVED INVALID

(Core :: XUL, defect)

Description

[Sören Hentzschel]

Setting the scrollbar color for sidebars via userChrome.css no longer works.

STR:

1. set toolkit.legacyUserProfileCustomizations.stylesheets to true
2. apply the following CSS
3. restart Firefox
4. open a sidebar

:root {
  scrollbar-color: #33CCFF #f2f2f2 !important;
}

Pushlog: https://hg-edge.mozilla.org/mozilla-central/pushloghtml?fromchange=bba8b54545d17d0a940a38bc4bb8877c4b04e7bb&tochange=7d880ff29269122bc521b3f69a643a3b7158a8eb

Unfortunately, due to bug 1959047 I cannot bisect further.

:emilio, there have been a few changes in the scrollbar area that you have implemented. Maybe you could have a look?

Comment 1

[Emilio Cobos Álvarez [:emilio]]

Which OS are you on? I can't repro this (on Linux). I tried scrollbar-color: red red !important for more visibility and it works as expected.

Comment 2

[Sören Hentzschel]

It was reported in the Firefox support by a Windows user and I can confirm the issue on macOS.

Comment 3

[Emilio Cobos Álvarez [:emilio]]

Ok, will try there.

Comment 4

[Emilio Cobos Álvarez [:emilio]]

Ok, sorry for the lag here.

So the key difference is whether you're in the modern sidebar or not (sidebar.revamp). This is because I tweaked the scrollbar rules to also apply to <xul:tree> scrollbars in bug 1982188.

Workaround is to change the CSS selector to have :root, scrollbar { ... } rather than just :root. I don't think I'm going to change the CSS to accommodate this use case tho.

Comment 5

[Sören Hentzschel]

Workaround is to change the CSS selector to have :root, scrollbar { ... } rather than just :root. I don't think I'm going to change the CSS to accommodate this use case tho.

That's useful information to work with. Anyone who customizes the interface via userChrome.css is used to having to adapt their code every now and then anyway. Thanks for taking a look!