lomiri: Logging out through GUI crashes desktop

Describe your issue

When running Lomiri on desktop, if a user tries to log out the desktop crashes.

What's the expected behaviour?

Logging out places user to login screen.

What's the current behaviour?

Logging out crashes the desktop.

How to reproduce your issue?

Start Lomiri, open the session applet, click "Log Out...", click the popup "Log Out".

What device are you using?

qemu-amd64

On what postmarketOS version did you encounter the issue?

• edge (feature/lomiri branch)

• v23.12

• v23.06 (supported until 2024-01-18)

• I confirm that the issue still is present after running sudo apk upgrade -a

On what environment did you encounter the issue?

Environments

• GNOME Shell on Mobile
• Phosh
• Plasma Mobile
• Sxmo (Wayland/Sway) Please post the output of sxmo_version.sh
• Other: Lomiri

How did you get postmarketOS image?

• from https://images.postmarketos.org
• I built it using pmbootstrap
• It was preinstalled on my device

What's the build date of the image? (in yyyy-mm-dd format)

Most likely Lomiri expects lightdm to be running so it can properly log the user out. Since we use tinydm on postmarketOS, Lomiri probably has no idea what to do and panics.

Additional information

Lomiri seems to stop correctly. I assume that since there is no real login-screen present nothing happens after Lomiri stops.

<information> mirserver: Stopping
<information> xwayland: XWayland stopped
qtmir.screens: QtCompositor::stop