1852198 - backdrop-filter breaks bottom rounded corners on Linux

Status: NEW

(Core :: Graphics: WebRender, defect)

Description

[abrarsl2002]

Attachment: Screenshot from 2023-09-08 10-58-02.png

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/119.0

Steps to reproduce:

Installed Firefox Nightly (119.0a1 (2023-09-06) (64-bit)) from a flatpak repo (https://gitlab.com/projects261/firefox-nightly-flatpak). I'm also using wayland.

Go to either twitter.com or mastodon.social

Actual results:

The body of the website overlaps the rounded corner at the bottom of the window.

Expected results:

The content should not have overlapped the window corner.

Comment 1

[abrarsl2002]

This is related to https://bugzilla.mozilla.org/show_bug.cgi?id=1850827 of course.

Comment 2

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

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 3

[abrarsl2002]

The bug can also be reproduced at https://vanillaos.org/ and https://usebottles.com/

Comment 4

[Martin Stránský [:stransky] (ni? me)]

Emilio, any idea here?
Thanks.

Comment 5

[Emilio Cobos Álvarez [:emilio]]

It works if I remove backdrop-filter from the site's CSS.

Glenn, does backdrop-filter assume web content is unclipped somehow? Is there a better way to implement the bottom rounded corners that doesn't suffer from this?

Comment 6

[Glenn Watson [:gw]]

It should work fine with clipped web content, sounds like just a bug that will need investigation I think.

Leaving a breadcrumb for when I or someone else looks at it in more detail - perhaps when we promote a backdrop filter container to be a picture cache slice, we don't check if there is a rounded rect corner on the picture cache root or something like that?