1705460 - My daily got into an state in which it had the "default theme" on linux, but still had non-native scrollbars (other code thought that I had a non-default theme enabled)

Status: RESOLVED FIXED

(Thunderbird :: Theme, defect)

Description

[Emilio Cobos Álvarez [:emilio]]

See the title...

A couple weeks ago I noticed my scrollbars in Daily were square in one of my machines (but not in the other). Both use the system theme. Today I'm using that machine again and decide to dig a bit...

It's because of these rules, but of course those should only apply when a non-default theme is applied.

Now the issue is that switching themes and back fixed it, so I can't reproduce anymore :(. But filing just in case this rings a bell and you can see what might go on.

This is using the "Arc Dark" GTK theme, which is dark. So maybe some code got confused and tried to apply the default dark theme or something like we do on windows?

Comment 1

[Emilio Cobos Álvarez [:emilio]]

Oh! They're back to square. That's odd, but hopefully I can help diagnose!

Comment 2

[Emilio Cobos Álvarez [:emilio]]

Attachment: screenshot (that's using system colors but still non-native scrollbars)

Comment 3

[Alessandro Castellani [:aleca]]

Uh, why the spam icon is black? 😢

Comment 4

[Emilio Cobos Álvarez [:emilio]]

The "all mail" icon is also black, in both my installations (the "good" and the "bad" one, when there's no remaining mail). A few other icons are also black. Do you know where are those defined? When I inspect that part of the UI I only get to the <treechildren>

Comment 5

[Alessandro Castellani [:aleca]]

Yeah, those are defined here: https://searchfox.org/comm-central/rev/fcb2f819cde716b9ed6596168f5a0498819b88a0/mail/themes/shared/mail/folderPane.css

They can't be inspected directly because of the "beauty" of XUL tree :P

Comment 6

[Emilio Cobos Álvarez [:emilio]]

Yeah, so these don't match on the default linux theme, because it's not a lightweight theme.

So for that you want something like:

@media (prefers-color-scheme: dark) {
  :root:not(:-moz-lwtheme) {
      --default: #dcdcdc;
      --primary: #45b1ff;
  }
}

Or such. Though after https://phabricator.services.mozilla.com/D111486 you should be able to just write:

@media (-moz-toolbar-prefers-color-scheme: dark) {
  :root {
    ...
  }
}

And remove the first rules.

Comment 7

[Emilio Cobos Álvarez [:emilio]]

Attachment: scrollbars.patch

We apparently set the lwt-tree* attributes even on the default theme:

https://searchfox.org/comm-central/rev/3a01c489963cb3bc423bb3b78e9cbecbec6b99fe/mail/base/content/toolbarIconColor.js#131-164

It's a bit sketchy to set lwt-* attributes when there's no theme, maybe the lwt-* prefix should be removed. But this is the right fix anyways.

Comment 8

[Emilio Cobos Álvarez [:emilio]]

Attachment: unread.patch

This fixes the color of the unread icons, see the commit description for details.

Comment 9

[Alessandro Castellani [:aleca]]

Comment on attachment 9216614 [details] [diff] [review]
scrollbars.patch

Thank you so much for taking care of these.
I'll redirect these reviews to Richard, which is the Theme module owner and can properly test these changes on al platforms.

Comment 10

[Richard Marti (:Paenglab)]

Comment on attachment 9216614 [details] [diff] [review]
scrollbars.patch

Yes, this makes sense.

Comment 11

[Richard Marti (:Paenglab)]

Comment on attachment 9216615 [details] [diff] [review]
unread.patch

Why does this works? We have other places in this file where we only set the fill and they are working. Should we change them to color: x; and set the fill: currentColor; on the main rule?

Many thanks for fixing both issues!

Comment 12

[Emilio Cobos Álvarez [:emilio]]

Setting fill works usually. The problem is that that variable is "inherit", and inheriting fill is not the same as inheriting color.

Comment 13

[Richard Marti (:Paenglab)]

I'll set c-c so it will be landed.

Comment 14

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/25eb8425f3ab
Don't set scrollbar-colors when using the system theme. r=Paenglab
https://hg.mozilla.org/comm-central/rev/b7937efa808c
Fix unread folder icon color. r=Paenglab