GNOME Panel & Activities Overview workspace thumbnails flickering issue
https://askubuntu.com/questions/1567665/gnome-panel-activities-overview-workspace-thumbnails-flickering-issue
GNOME Activities Overview workspace thumbnails begin flickering after several hours of uptime on Ubuntu 26.04 LTS with GNOME Shell 50.1 running on Wayland and Intel Alder Lake-N integrated graphics (i915 driver).
System:
- Ubuntu 26.04 (upgraded from 24.04)
- GNOME Shell 50.1 / Mutter 50.1
- Wayland session (no Xorg session available)
- Intel Alder Lake-N UHD Graphics (i915 driver)
- Three displays (all 1920×1080 @ 60Hz)
Symptoms:
- After several hours of uptime, GNOME Activities Overview becomes visually corrupted.
- Specifically, workspace thumbnails flicker immediately upon entering Overview (Super key or hot corner).
- The flickering is limited to Overview workspace thumbnails and GNOME top bar. Normal desktop, application windows remain stable and unaffected.
- Exiting Overview immediately returns the desktop to normal.
Logging out and back in resolves the issue temporarily, but it returns in minutes, rebooting it returns after several hours.
No GPU resets, hangs, or DRM errors appear in journalctl.
I’ve tried:
- Kernel parameter: intel_idle.max_cstate=1
Appears to delay or partially change the symptoms, but the issue still occurs.
- Kernel parameter: i915.enable_dc=0
Initially seemed to reduce symptoms, but the issue still returned.
- Tested different kernels (including older kernel)
No change in long-term behavior.
- Disabled a couple of third-party GNOME extensions (still using default Ubuntu extensions).
Observations:
- The issue does not affect application rendering or the desktop outside of Activities Overview.
- It appears only after extended uptime (hours), not immediately after login.
- The issue is reproducible across reboots and kernel versions.
- No relevant errors in journalctl related to i915, DRM, or GPU resets.
Question:
Has anyone seen GNOME Activities Overview workspace thumbnail flickering or corruption on GNOME Shell 50 / Mutter 50 under Wayland, particularly on Intel integrated graphics? Are there known issues, workarounds, or logs that I should investigate further?
Update:
I performed additional testing and found a significant correlation with monitor configuration.
With my original multi-monitor setup (2 ASUS monitors + 1 TCL TV), GNOME Shell produced thousands of repeated errors:
gbm_surface_lock_front_buffer failed
Failed to query buffer age, got error 3003
These sessions also exhibited Activities Overview flickering, top-panel flickering, and occasional window-edge artifacts.
I have now tested the system with a single display only (different display: Sony TV over HDMI) and the issue has not reproduced. There is no visible flickering, no rendering corruption, and:
journalctl -b | grep -c "gbm_surface_lock_front_buffer failed"
0
journalctl -b | grep -c "Failed to query buffer age"
0
The issue also reproduced across multiple kernels, including a newer mainline kernel Linux 7.0.12-070012-generic, which makes a pure kernel/i915 explanation seem less likely. Using this mainline kernel the symptoms also started appearing after roughly 10 minutes rather than a few hours.
At this point, the strongest lead appears to be a GNOME Shell/Mutter multi-monitor rendering issue, or an interaction involving multiple outputs.