1616663 - Menu hover effect is off-by-one with WebRender

Status: RESOLVED DUPLICATE of bug 1567791

(Core :: Graphics: WebRender, defect, P3)

Description

[Victor Zamanian]

Attachment: firefox-webrender-menu.mp4

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:73.0) Gecko/20100101 Firefox/73.0

Steps to reproduce:

1. Enable WebRender via about:config -> gfx.webrender.all = true
2. Open hamburger menu or "Page actions" menu in address bar
3. Move mouse pointer over menu items

This does not happen when I turn off WebRender.

This is on Linux, using an Nvidia GeForce GTX 1060, proprietary driver version 440.59.

Actual results:

Menu items are highlighted in an off-by-one fashion, so that hovering over one item does not highlight that item until you move the mouse pointer to another menu item. See the attached clip of it in action.

Expected results:

The menu item which is currently hovered is the one which should be highlighted.

Comment 1

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

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Comment 2

[Andrew Osmond [:aosmond] (he/him)]

This doesn't look like a snapping issue, since from the video, it appears to be many pixels off. I could not reproduce on release/nightly. Does it happen with nightly still? Do you use any scaling? What desktop environment? GNOME, KDE? I assume not Wayland. about:support would be welcome. Might boil down to the proprietary driver (if it is easy to test with Nouveau or an Intel GPU with your setup, that would be handy to know). Thanks!

Comment 3

[Victor Zamanian]

(In reply to Andrew Osmond [:aosmond] from comment #2)

This doesn't look like a snapping issue, since from the video, it appears to be many pixels off.

I'm not sure what "snapping" refers to here but I'm guessing this wasn't directed at me. :-) But yes! It's several pixels off: a menu item is only highlighted when the mouse cursor touches the first pixel (from some direction/dimension) of another menu item. A menu item is also highlighted when it receives a click event:

• Mouse1 (left-click) immediately highlights the menu item on mousedown.
• Mouse3 (middle click) highlights the menu item on mouseup.
• Mouse2 (right-click) does not highlight the menu item on click.

I could not reproduce on release/nightly. Does it happen with nightly still?

Yes, I got the exact same behavior on Firefox Nightly (version "75.0a1 (2020-02-24)").

Do you use any scaling?

At work I use the following:

export GDK_SCALE=1.5
export GDK_DPI_SCALE=1.5

as well as Xft.dpi: 110 in ~/.Xresources.

At home I don't use any such GDK scaling, but there I do use Xft.dpi: 82.

What desktop environment? GNOME, KDE? I assume not Wayland.

I am not running Wayland, but X. I'm running Arch Linux with the i3 window manager, and mostly GNOME apps. So technically no desktop environment, but I have these envars:

export DE=gnome
export XDG_CURRENT_DESKTOP=$DE

about:support would be welcome.

• Firefox 73.0.1 plain text
• Firefox 73.0.1 JSON
• Firefox Nightly 75.0a1 plain text
• Firefox Nightly 75.0a1 JSON

(I hope I got all those links right. Please let me know if something's wrong and I'll try to provide the correct information!)

Might boil down to the proprietary driver (if it is easy to test with Nouveau or an Intel GPU with your setup, that would be handy to know). Thanks!

At home I'm using proprietary Nvidia driver version 440.59. At work I'm using integrated graphics, I believe:

~ % lshw -numeric -C display
WARNING: you should run this program as super-user.
  *-display UNCLAIMED       
       description: 3D controller
       product: GP107M [GeForce GTX 1050 Mobile] [10DE:1C8D]
       vendor: NVIDIA Corporation [10DE]
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: bus_master cap_list
       configuration: latency=0
       resources: memory:ec000000-ecffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:ed000000-ed07ffff
  *-display
       description: VGA compatible controller
       product: HD Graphics 630 [8086:591B]
       vendor: Intel Corporation [8086]
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 04
       width: 64 bits
       clock: 33MHz
       capabilities: vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:144 memory:eb000000-ebffffff memory:80000000-8fffffff ioport:f000(size=64) memory:c0000-dffff

I have disabled the GTX 1050 on my work laptop as it wasn't working properly with the proprietary drivers. I don't have nouveau installed.

Please let me know if there's any more info you need! Thanks for looking into this!

Comment 4

[Jessie [:jbonisteel] pls NI]

Was chatting with Andrew this morning, and we suspect this is not snapping, perhaps something with hit testing. Worth also double checking if this happens on Win10

Comment 5

[Dominik Mierzejewski]

I can reproduce this as well with FF73+ (currently: 75.0) on Fedora 31 running MATE on X11. Only open-source drivers are installed in my case (Intel Haswell on one machine and Radeon on another). Do you need about:support from my machines as well?

Comment 6

[Darkspirit]

This is a known Linux bug: bug 1567791.
At the moment there are only 3 other Linux bugs that actually matter: bug 1611372, bug 1628685 (basically all the same Nvidia bugs), bug 1502519