GNOME Activities Overview workspace thumbnails begin flickering after about 10 minutes 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 about 10 minutes 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 a few minutes, rebooting it returns after 10 or 15 minutes. 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. - Update - this occurs sporadically, sometimes 10 minutes and some boots it would take a few hours.
- 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.
Update (June 22nd):
The issue now consistently appears ~10 minutes after boot (earlier testing likely just didn’t run under full load).
The “unplug/replug” suggestion didn’t help, but it led to a reliable workaround: boot with only the DP 4K display connected, wait a few minutes, then connect the first HDMI display, wait again, then connect the second HDMI display. This results in a stable session and has provided ~20 hours of uptime without flickering or GBM errors.
I’ve reverted all system tweaks and returned displays to:
DP-1: 3840×2160 @ 60Hz, 200% scaling HDMI-1: 3840×2160 @ 60Hz, 200% scaling HDMI-2: 1920×1080 @ 60Hz, 100% scaling
(Previous all at 1080p configuration was part of testing.)
Driver and desktop tests:
Tried Intel Xe driver → same issue Tried KDE Plasma and Budgie → no flickering/GBM errors, but DP 4K display stayed black until forcing 30Hz via CLI (GUI wouldn’t allow it), so I reverted back to GNOME
Current conclusion: GNOME + Intel display stack on this hardware appears unstable only in full 3-display configurations. Any 1–2 display combination is stable for long periods, but stability on 3 displays only occurs with the staged hotplug sequence (DP first, then HDMIs). Adding DP last reliably triggers the issue.
At this point, this is a workaround rather than a fix.