1770767 - White pane on dark wikipedia

Status: RESOLVED INVALID

(Firefox :: Untriaged, defect)

Description

[Blake]

Attachment: white wikipedia.PNG

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0

Steps to reproduce:

1. Login to Wikipedia
2. Click "Preferences"
3. Click "Gadgets"
4. Enable "Dark Mode"
5. Enable "Core Styling"

Actual results:

Wikipedia's entire left pane is white

Expected results:

Wikipedia's entire left pane should be dark

Comment 1

[Blake]

According to mozregression:

DEBUG : Found commit message:
Bug 1423746 - Filter on root should not establish containing block for fixedpos elements. r=mstange

Teach nsDisplay{Filters,BackdropFilters} to use a style that doesn't
belong to mFrame for the root frame, and use it as needed.

Remove the BackdropFilters::CanCreateWebrenderCommands call because it
was testing for StyleSVGEffects::mFilters rather than mBackdropFilters,
so it was doing nothing.

Differential Revision: https://phabricator.services.mozilla.com/D146188

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1423746

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

:emilio, since you are the author of the regressor, bug 1423746, could you take a look?
For more information, please visit auto_nag documentation.

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Thanks for filing. They have a firefox-specific hack that, when applied, shows the same issue in other browsers:

@-moz-document url-prefix() {
 body {
  background:#000;
 }
}

When removed, Firefox behaves correctly. So this needs to be brought up to Wikimedia instead.

In order for it to work on both older and newer versions of Firefox (and actually this shouldn't need to be browser-specific at all) they could use:

:root, body {
  background-color: white;
}

I'll try to send them a patch.

Comment 5

[Emilio Cobos Álvarez (:emilio)]

I think I did it right but if you're familiar with mediawiki processes it'd be great: https://en.wikipedia.org/wiki/Wikipedia_talk:Dark_mode_(gadget)#Interface-protected_edit_request_on_23_May_2022_%28Change_%2F_remove_Firefox_hack%29