No GUI apps start with any user (root included)

Environment

Windows build number: Microsoft Windows [Version 10.0.21376.1]
Your Distribution version: Release:        20.04
Your WSLg version: 1.0.19

Steps to reproduce

Run any GUI application from the wsl terminal.

WSL logs:

• Attach WSLg logs from /mnt/wslg

You can access the wslg logs using explorer at: \\wsl$\<Distro-Name>\mnt\wslg (e.g.: \\wsl$\Ubuntu-20.04\mnt\wslg)

pulseaudio.txt
weston.txt

• versions.txt

WSLg ( x86_64 ): 1.0.19+Branch.main.Sha.2a47bf20c239b523d7413f315cbc9ee60dfde831
Mariner: VERSION="1.0.20210224"
FreeRDP: 5f083fa0b97d433d6204985f6047886e29c1c61e
weston: 16de531f00aa3dfd17e0de74c8f49e9fd7cec617
pulseaudio: 2f0f0b8c3872780f15e275fc12899f4564f01bd5
mesa:

Expected behavior

A graphical application (like xclock, gedit etc) should start when called from the wsl terminal.

Actual behavior

None of the applications run. The wsl terminal gets blocked but nothing else happens.

Start by reproducing the issue from a WSL terminal with a GUI application such as xclock or gedit, then inspect the attached pulseaudio.txt and weston.txt logs under /mnt/wslg along with versions.txt. Done means GUI applications start for users, including root, without blocking the terminal.