1411398 - Firefox menus are misplaced after monitor reconfiguration

Status: UNCONFIRMED

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

Description

[gpothier]

Attachment: firefox-bug.mp4

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171024001719

Steps to reproduce:

Computer has two monitors configured (laptop's + external). Open Firefox. Then unplug the external monitor. Click on UI elements that cause a popup menu to appear (eg. right click to display context menu, click on bookmark folder, or on "burger" menu icon)


Actual results:

The popup menus appear at seemingly random locations. Moreover, the menu item highlighting do not match the actual mouse position (see attached video).
Happens on v56 and v57 beta.


Expected results:

The popup menus should appear at their correct location: right next to the mouse cursor for context menu, or next to the UI element that triggers the popup).

Comment 1

[gpothier]

Original bug report in Ubuntu: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1721614

Comment 2

[gpothier]

The bug is still present in v58.0b11. I'll try to give more precisions. As I wrote earlier, pop up menus appear at incorrect locations after reconfiguring monitors. As shown in the attached video, they can appear quite far away from their correct location. Maybe an important point is that the DPI settings change between configurations. One configuration is with only the internal laptop monitor at 3200 x 1800 with high DPI settings, and the other one is internal + external monitor, both at 1920 x 1080 (normal DPI settings).

It seems there is some kind of caching of individual menu positions, and this caching seems to be invalidated when the requested menu position changes; afterwards the menus appear in their correct positions until the next monitor reconfiguration. This invalidation can be triggered in two ways:

- For the context menu (right click), simply closing the menu and right clicking somewhere else solves the problem. The context menu is thus misplaced only once after reconfiguring the monitors (unless one right clicks again at the exact same position)

- For the bookmarks and search menus, one has to move the window by a few pixels in order to get rid of the problem. However, it is necessary to open each menu once before moving the window to get rid of the problem for that particular menu. For instance with two bookmarks menus, after reconfiguring the screens I open the first one, it is misplaced. Then I move the window and open the first menu again, then it is correctly placed. However if after that I open the second menu, it is also misplaced. I have to move the window again to fix it. On the other hand, if after reconfiguring the screens I open both menus (both are then misplaced) and then move the window, after that both menus are correctly placed.

Comment 3

[gpothier]

Following up on this report: this bug is 100% reproducible with the Ubuntu 18.04 Live usb image, so it is not a configuration/package issue on my system.

Steps to reproduce:
0. Use a laptop with high resolution display (eg. 3200 x 1800).
1. Boot from live image with external monitor plugged in.
2. Launch Firefox and enable the bookmarks toolbar.
3. Open and close the first item in the toolbar (or any other menu actually) => no problem.
4. Open the display configuration app and change config, eg. change scale from 200% to 100%, or change built in display's resolution to 1900 x 1080.
5. Open the first item in Firefox's bookmarks toolbar => it usually appears at wrong location. If not, try disconnecting the external monitor and opening the menu. At some point it will appear at the wrong location.

Comment 4

[gpothier]

I did a bisection and found that the problem started appearing here:

13:29.43 INFO: Last good revision: 8e5c888d0d89 (2015-07-22)
13:29.43 INFO: First bad revision: 1f77b78797d6 (2015-07-23)

I think it has to do with DPI handling, as in the last good revision the whole UI appears very small on the laptop's built in high DPI display, and in the first bad revision it seems work was being done to address this. Unfortunately I could not go deeper than nightlies:

18:02.59 INFO: There are no build artifacts on inbound for these changesets (they are probably too old).

Comment 5

[Yiannis]

I've been having the same problem for a while. It is exactly as gpothier described. It is really an annoyance as the only way to get back to work normally, is to basically quit Firefox and start it up again.
I'm using Fedora 28, but the problem was the same on Fedora 27. I tested Fedora 29 too. Would be really nice to have to bug fixed at some point. If can provide any more info about the problem, please let me know.

Comment 6

[Stergios]

I have the same problem in both Fedora 29 and Ubuntu 18.04. Would really appreciate a fix.

Comment 7

[Alireza Haghshenas]

I have the same problem:
Firefox 95.0.2 (64-bit)
Operating System: Fedora Linux 35
KDE Plasma Version: 5.23.3
KDE Frameworks Version: 5.89.0
Qt Version: 5.15.2
Kernel Version: 5.15.10-200.fc35.x86_64 (64-bit)
Graphics Platform: Wayland

Monitors:
Frame.work laptop (2256*1504@100%)
Dell 32"4k@150%

The right click menu in many pages including Google search results are not shown, but are there somehow. So if I press escape to close the invisible menu and right-click again and repeat this several times, the context menu will eventually be shown.