Felix Miata wrote:
Whether what I did might work for others may depend on the distro used and/or whether or how plymouth is configured and/or installed. None of my installations have plymouth installed except for Mageia, which is unusable if plymouth installation is disallowed. In Mageia I include plymouth.enable=0 or noplymouth on Grub's kernel cmdline and/or disable plymouth with systemctl.
For purposes of this thread, /etc/systemd/system/tdm.service did not exist. I copied it from /lib/systemd/system/ and then modified it. IIRC, I was using Bullseye only, not Buster as I wrote in OP.
Always better to test on default setup - I am not sure if plymouth is installed by default, but I tested on a fresh installed Debian and this exactly solved the problem. It was also confirmed in the original bug report. No need to further muddy the waters.
What I understand is perhaps it is a plymouth related. If I have the time I would do some testing, find the bug and update there.
regards