Waydroid Crashes When Moving Cursor to Window or Enabling "Show Taps" After Updating to 20250503 Image or Later

Steps to Reproduce

1. Install or update Waydroid to the 20250503 image or any later version.
2. Either:
   • Move the mouse cursor into the Waydroid window, or
   • Enable Show Taps in the Android developer options.

Expected Behavior

Waydroid should function normally without crashing.

Actual Behavior

• Waydroid crashes and restarts itself.
• In some cases, it also causes the Lomiri desktop to crash.

Affected Devices

• Any devices running Ubuntu Touch
• Any devices running Lomiri Desktop

Additional Details

The issue appears to be related to how Lomiri handles drawing cursors or tap indicators on the Waydroid window.

On my Fairphone 4 running Ubuntu Touch (Focal), Waydroid functioned normally with Show Taps enabled on images up to 20250426. However, after updating to the 20250503 image (or any newer image), Waydroid started crashing when interacting with the window, especially when touch input was used.

Initially, I wasn't sure what triggered the crash, but after wiping the Waydroid container and starting fresh, I discovered that enabling Show Taps immediately caused Waydroid to crash again. This confirmed that Show Taps was the culprit.

To cross-check, I tested another device running Droidian with Waydroid. After updating to the 20250503 image, enabling Show Taps worked as expected and correctly displayed touch indicators. No crash occurred. This suggests the issue is likely specific to Lomiri-based environments.

Another user also face the same issue when using an external mouse in desktop mode on the Fairphone 4:
Waydroid crashes in Desktop Mode over HDMI

Their testing showed that simply moving the mouse cursor into the Waydroid window triggered a crash.

This issue is not limited to the Fairphone 4. On my Surface Go 3 running Ubuntu Lomiri 24.04 LTS (via Ubuntu Unity), the same crash happens when moving the cursor into the Waydroid window after updating to the 20250503 image or later.

For further testing, I installed ubuntu-desktop (Vanilla Ubuntu desktop powered by GNOME with Wayland) on top of Ubuntu Lomiri on my Surface Go 3. When switching to the GNOME desktop and launching Waydroid, the crash does not occur. Waydroid runs normally even when using a mouse.

Conclusion

This crash appears to be specific to the Lomiri desktop environment and affects Waydroid builds starting from 20250503 and later. The issue is likely related to how Lomiri handles cursor rendering or gesture overlays in the updated Waydroid builds. Environments running GNOME with Wayland do not experience this problem.