Tiling left, right, fullscreen results in incorrect bottom gap on laptop screen when laptop (UHD) is connected to monitor (FHD) from boot

[Rend0e]

Describe the bug Whenever I boot my laptop (UHD 4k screen 16:10) with my monitor (FHD 1920x1080p 16:9) screen, tilling any windows left, right or fullscreen on the laptop display results in incorrect bottom gap. Tiling left/right corner and down does not have the issue. The issue goes away when I unplug then replug my monitor however it comes back upon reboot (if monitor is connected during boot). Issue happens on both 1920 x 1200 (16:10) and 4k (16:10). This only occurs when I connect my monitor to my laptop from boot. Maybe because my laptop aspect ratio is 16:10 while my monitor is 16:9.

Steps To Reproduce Plug monitor when system starts, til any window left, right, full screen will result in the incorrect bottom gaps. Tilling left/right corner or down does not create the incorrect bottom gaps.

https://user-images.githubusercontent.com/20853575/182545028-b982bf49-ebb0-4da4-8347-e5b7622202d6.mp4

System Info:

• Distro (incl. version): Arch
• GNOME (Shell) version: Gnome 42.3.1
• Extension version and from where (e. g. EGO, main branch...): main
• XOrg/Wayland: Wayland

Journalctl logs Error in size change accounting whenever a window is tilled (even after unplugging and replugging the monitor)

[Leleat]

I noticed a similiar issue when I was fixing that gap issue on non-100% scaled displays (only tested a single monitor setup in a VM). For me however there was a gap around the entire window (not just on the bottom part). But it didn't apply to all windows. Some apps actually tiled correctly; altough I don't remember which apps.

Can you see if it's the same issue (i. e. try to reproduce it with a scale of 100%)?

[Rend0e]

The issue occurs for both 1080 x 1200 100% and 4k 200% only when connected to another monitor from boot, seems like QT apps and electron apps aren't affected upon more testing

[jessicarod7]

I'm seeing a similar issue when Chrome is tiled on the border connecting the different resolution displays. If I switch workspaces or open the Activities screen, the Chrome window will remain tiled but become slightly larger and overflow into the other screen. Also seeing Error in size change accounting whenever a window is tiled.

• Before:
  • 
• Activities overview:
  • 
• After:
  • 

Display layout:

• Display 1: 3456 x 2160 (16:10) at 200% scaling
• Display 2: 2560 x 1440 (16:9) at 100% scaling, main display

System Info:

• Distro (incl. version): Fedora 36
• GNOME (Shell) version: Gnome 42.3
• Extension version and from where (e. g. EGO, main branch...): EGO
• XOrg/Wayland: Wayland

[Leleat]

I am trying to reproduce this with my laptop (1900x1200 at 100%) and my external monitor (3440x1440 at 200%) but I don't think I can. I only found an issue when I switch the the (external) monitor from 100% (at boot) to 200% under X. That bug seems kinda similiar. Some windows get a gap around the entire window under some tiling conditions. Maybe it's the same issue or at least related, not sure...

Anyway, considering you say this happens when you boot with an external monitor connected during boot and that it only affects some windows, it's probably not a bug in my extension. And thus probably unfixable for me 😕. Maybe it's a mutter bug or a GTK one. I don't know... I am too unknowing in that area to be able to tell.

PS.

seems like QT apps and electron apps aren't affected upon more testing

in the issue I discovered it wasn't even consistent among GTK apps (i. e. only some GTK/Libadwaita apps had the issue).