Windowing tiling issue on 16:9 aspect ratio monitor

[da-022412]

(1) Issue/Bug Description: I have a 16:9 3440x1440 resolution monitor and am using the tiling window manager. When I have three windows open in one workspace and I minimize one of the windows, everything works as expected. Now, when I go to close one of the windows, it closes, but behaves as if it is still open. So the remaining window is still open, but it only encompasses half of the screen. I'll then open the minimized window and it will behave as if there are three windows, only encompassing 1/4 of the screen.

(2) Steps to reproduce (if you know): Open 3 windows in tiling mode on a 3440x1440 16:9 monitor. Minimize one of the windows, and close another one. Open the minimized window.

(3) Expected behavior: Upon opening minimized window, it should encompass half the screen.

(4) Distribution (run cat /etc/os-release): NAME="Pop!_OS" VERSION="20.04 LTS" ID=pop ID_LIKE="ubuntu debian" PRETTY_NAME="Pop!_OS 20.04 LTS" VERSION_ID="20.04" HOME_URL="https://pop.system76.com" SUPPORT_URL="https://support.system76.com" BUG_REPORT_URL="https://github.com/pop-os/pop/issues" PRIVACY_POLICY_URL="https://system76.com/privacy" VERSION_CODENAME=focal UBUNTU_CODENAME=focal LOGO=distributor-logo-pop-os

(5) Gnome Shell version: gnome-shell --version GNOME Shell 3.36.7

(6) Pop Shell version (run apt policy pop-shell or provide the latest commit if building locally):

apt policy pop-shell
pop-shell:
  Installed: 1.1.0~1620418263~20.04~9507dc3
  Candidate: 1.1.0~1620418263~20.04~9507dc3
  Version table:
 *** 1.1.0~1620418263~20.04~9507dc3 1001
       1001 http://ppa.launchpad.net/system76/pop/ubuntu focal/main amd64 Packages
       1001 http://ppa.launchpad.net/system76/pop/ubuntu focal/main i386 Packages
        100 /var/lib/dpkg/status

(7) Where was Pop Shell installed from: Official

(8) Monitor Setup (2 x 1080p, 4K, Primary(Horizontal), Secondary(Vertical), etc): 3440x1440 1440p 16:9

(9) Other Installed/Enabled Extensions: Alt Tab: Raise First Window Always Show Workspaces Desktop Icons NG Pop Shop Details System76 Power Ubuntu AppIndicators

(10) Other Notes:

[mmstick]

Which applications?

[da-022412]

All applications

[mmstick]

Can't replicate on GNOME 3.38 at least

[da-022412]

I've attached a gif of me recreating the issue in a support ticket created via system76 website. Case #60517

[mmstick]

I don't have access to support tickets

[da-022412]

Would the gif help? If so, how can I send?

[mmstick]

You can drag and drop the gif into your comment to place an image or file in your comment.

[da-022412]

[mmstick]

So it's a certain series of window movements that triggers a bad state in the window tree. I was able to get similar to happen after a while of moving windows around.

[da-022412]

Awesome. Does this also occur on other monitor resolutions?

[mmstick]

The only effect resolutions have on the tree is the calculated areas for nodes in the tree. This is an issue with node creating and destruction where the tree gets in an inconsistent state that has two nodes with the same window entity attached to it, which causes a node to be allocated to a window that is already assigned or may no longer exist.

[da-022412]

Got it, thank you!

[amituttam]

Chiming in. I see the similar behavior on a 16:10 laptop display, where the single application only takes half the screen.

$ cat /etc/os-release
NAME="Pop!_OS"
VERSION="21.04"
ID=pop
ID_LIKE="ubuntu debian"
PRETTY_NAME="Pop!_OS 21.04"
VERSION_ID="21.04"
HOME_URL="https://pop.system76.com"
SUPPORT_URL="https://support.system76.com"
BUG_REPORT_URL="https://github.com/pop-os/pop/issues"
PRIVACY_POLICY_URL="https://system76.com/privacy"
VERSION_CODENAME=hirsute
UBUNTU_CODENAME=hirsute
LOGO=distributor-logo-pop-os```

For pop-shell I built from git HEAD to see if it helps but I notice the same behavior. Let me know if you need additional information.

[marksumm]

This was the main reason I stopped using pop-shell on 20.04 but I didn't know how to put it into words. It seemed impossible that no-one else was seeing it. It's as if the empty screen area perceived by pop-shell gets smaller and smaller over time, leading to the creation of unusable tiny windows and big gaps that can't be used for tiling. Normal behaviour can be restored by restarting the window manager, but that has undesirable consequences: The layout of tiled windows changes randomly (and usually badly) and stacks collapse into separate windows.

[pcn]

This is still happening in 22.04. Is there any way to diagnose what's going on? When this happens I disable tiling and re-enable it and have to replace windows across a number of virtual desktops/workspaces and it is tedious.