GDM wayland login -- display shuts down and is hard to get on again
Since a few months I have GTK 3.22 on my gentoo box, and so I tried to
log in with Wayland support from the graphical GDM display manager.
Works all fine. But one problem is, that the display is shut down after
a few hours sometimes. Initially I had the impression that wayland does
that shut down. But the Gnome screensaver related settings are
disabled, and I never saw that shutdown without wayland.
My current impression is: Monitor shuts down after some hours to save
energy, wayland display driver detects this and shuts down the display
driver in PC to save even more energy. I think that is the right idea,
as the same seems to occur also when I power off the monitor while the
PC is still running.
Getting the display on again is really hard. After much testing a found
one method that works most of the time: Ensure monitor is powered off.
Then press Ctrl-ALT-F3. Wait about one second and switch on the
monitor. Most of the time I can get a visible terminal 3 this way and
can switch back to Gnome GUI with Alt-F2.
May there exist a better solution? A secret wakeup key? Or useful
search terms for search engine? Monitor is connected via USB-C to PC,
PC is Intel NUC skull canyon.