Debian 12.6: Screen won't come back on if monitor is power cycled

[Johan Sjölin]

Hi!

Since upgrading to Debian 12.6, I've started to experience a very
strange problem with my monitor. If I turn it off and later turn it on
again, the screen won't come back on (no signal). Doesn't help if I
press a key or a mouse button. The only way to recover from the blank
screen situation is by pressing CTRL + ALT + F1 (which returns me to the
GNOME login screen). I never had any similar problem before, either with
earlier versions of Debian or multiple versions of Ubuntu.

Screen blanking is turned off.

My desktop computer (Intel NUC7i5BNK) is hooked up by DisplayPort to my
monitor.

Is there anyone else experiencing this problem?

[Kent West]

Post by Johan Sjölin
Hi!
Since upgrading to Debian 12.6, I've started to experience a very
strange problem with my monitor. If I turn it off and later turn it on
again, the screen won't come back on (no signal). Doesn't help if I
press a key or a mouse button. The only way to recover from the blank
screen situation is by pressing CTRL + ALT + F1 (which returns me to
the GNOME login screen). I never had any similar problem before,
either with earlier versions of Debian or multiple versions of Ubuntu.
Screen blanking is turned off.
My desktop computer (Intel NUC7i5BNK) is hooked up by DisplayPort to
my monitor.
Is there anyone else experiencing this problem?
--
Johan Sjölin

Try pressing a shift key a couple of times, and then blindly typing your
user password. My guess is that the screensaver/lock is wonky.

[Johan Sjölin]

Try pressing a shift key a couple of times, and then blindly typing your user password. > My guess is that the screensaver/lock is wonky.

Doesn't work. I don't use any screensaver or automatic screen lock.

Whenever I power cycle the monitor, I get the error message below (found
in journalctl):

jul 19 00:59:43 galaktikos gnome-shell[1748]: Failed to create colord
device for 'xrandr-Samsung Electric Company-S27E650-H4ZH102483': failed
to obtain org.freedesktop.color-manager.create-device auth

[d***@howorth.org.uk]

Post by Johan Sjölin

Post by Kent West
Try pressing a shift key a couple of times, and then blindly typing
your user password. > My guess is that the screensaver/lock is
wonky.

Doesn't work. I don't use any screensaver or automatic screen lock.
Whenever I power cycle the monitor, I get the error message below
jul 19 00:59:43 galaktikos gnome-shell[1748]: Failed to create colord
failed to obtain org.freedesktop.color-manager.create-device auth

There's a thread at https://bbs.archlinux.org/viewtopic.php?id=228663
that might be relevant?