Hello @madworm, that read like libcef is failing to initialize. If you completely close Steam, and run steam from a terminal without using su, are there any hints in the terminal spew while it misbehaves? It would also be interesting to check cef_log.txt steamwebhelper.log, and webhelper.txt in ~/.local/share/Steam/logs for any libcef-specific hints.
Also, it might be interesting to compare the environment variables that Steam sees in the working and broken cases. One way to view that is to run htop, select one of Steam's threads, and press e to view environment variables.
There were many dbus issues, most notably it referenced to "/var/lib/dbus/machine-id", a symlink to "/etc/machine-id", which inconveniently did not exist.
Since creating it with "systemd-machine-id-setup", so far, steam client starts happily without any special voodoo.
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
Steam client used to run just fine on my machine.
For some time now I just get an empty black window with just the menus and no content.
However! If I start the steam client the following way, it behaves normally:
This way it works, without the "su -l ..." part it doesn't. Different environment variables? I've created a new user from scratch, same behaviour.
Steps for reproducing this issue: