1725525 - layout.css.devPixelsPerPx greater than 1.0 causes cursor flickering jumping

Status: UNCONFIRMED

(Core :: Widget: Gtk, defect, P3)

Description

[jeffs chips]

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36

Steps to reproduce:

Cleared Firefox snap and standard directories from Ubunto 20.04 with firefox 91.0 (64-bit) machine due to unusable interface: mouse flickers and jumps over bookmarks making it unusable. Reinstalled snap. Everything worked fine until I about:config and changed layout.css.devPixelsPerPx to 1.2. Problem then returns.

Actual results:

Mouse flickers and jumps between bookmark menu items making it impossible to choose anything. Was forced to uninstall Firefox.

Expected results:

No flickering. Retain use of mouse properly.

Comment 1

[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 revert this change in case you think the bot is wrong.

Comment 2

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

Please attach content of about:support.
Thanks.

Comment 3

[jeffs chips]

Attachment: default

This bug seems intermittent.  I've included about:support first with default layout.css.devPixelsPerPx then set at 1.25.  As I write this the bug does not exist.  But it will pop up again at which point I will submit another about:support

First about:support as default layout:

Comment 4

[jeffs chips]

How do you clear a text submission? I am now trying to attach a file but first wish to clear or delete the previous submission. Thanks.

Comment 5

[Ernst Sjostrand]

Duplicate of bug 1789581 ?