Thanks for your prompt answer! I narrowed things down a bit. As I am using i3 wayland is not an option. I tried a live ubuntu 20.04 and could still reproduce the behaviour described. I went on to enable wayland in live session but failed eventually: XDG_SESSION_TYPE still yielded `x11` but in the process I restarted gdm3 -- and things were fixed. Okay, I went back to the os installed (regolith linux which is i3 based on ubuntu) and after restarting lightdm via systemctl, things are working as expected. That's weird.
Regarding your first question: It is HDMI indeed although xrandr claiming otherwise. There is an HDMI port beneath a DP at the rear and the rest of it is USB. Can I somehow convice the live system to run on wayland? The procedure described here: https://askubuntu.com/a/1258280/595512 did not work for me. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1915382 Title: external Monitor shows »No Signal« after dpms sleep To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1915382/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
