Precise reproduction steps identified: (atleast what I have noticed so far)
MST dual-CRTC display (5120x2160, Intel UHD 770) Reset to default experimental features: ['scale-monitor-framebuffer', 'xwayland-native-scaling'] Launch Telegram (Flatpak, Xwayland) or any Electron/X11 app via Xwayland → Immediate flickering at top corners, EGL errors begin Disabling "Built-in Scaling for Legacy Apps" (which disables xwayland-native-scaling) immediately stops flickering. Conclusion: xwayland-native-scaling + Xwayland app launch + MST dual-CRTC display = reproducible EGL buffer corruption. This is likely affecting all Ubuntu 26.04 users with tiled/MST displays since xwayland-native-scaling is in the default feature set. -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/2152207 Title: Failed to lock front buffer on /dev/dri/card1: gbm_surface_lock_front_buffer failed | Failed to query buffer age, got error 3003 To manage notifications about this bug go to: https://bugs.launchpad.net/mutter/+bug/2152207/+subscriptions -- desktop-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
