Bug 459038

SUMMARY
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After installing the latest KDE updates (I work with the unstable branch of Manjaro), when the active KDE session loses the HDMI signal, either because the session is switched by pressing Ctrl + (F1, F2, F3...), the monitor enters standby mode or because the signal is changed with a KVM switch, it is completely impossible to be able to recover the KDE session again, when it receives the HDMI signal again when changing back to the session by pressing Ctrl + (F1, F2, F3...), when leaving the monitor from standby or changing the signal to the computer with Linux on the KVM switch, the screen stays completely black and does not show the unlock screen, forcing you to open another console session with Ctrl + (F1, F2, F3...) to open another KDE session or directly being forced to restart the machine.

Please, this error is serious, I can't work this way, every time the monitor goes into standby mode because I get up to have a coffee or do something, when I come back I am forced to restart the machine, losing all my work that I have open.
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STEPS TO REPRODUCE
1. Switch to another console by pressing Ctrl + (F1, F2, F3...), waiting for the monitor to standby mode or switch to another machine via a KVM switch, anything that causes the current KDE session to lose HDMI signal

2. Trying to go back to the previous KDE session by pressing Ctrl + (F1, F2, F3...), moving the mouse to bring the monitor out of standby mode, or switching to the previous Linux machine via a KVM switch, anything that wakes up the HDMI signal in the previous KDE session.

OBSERVED RESULT

Then you will see that the KDE session does not react and the screen remains completely black, not being able to enter it again and being forced to restart the machine or open another console by pressing Ctrl + (F1, F2, F3...).

EXPECTED RESULT

Prior to installing the latest KDE updates, it would display the unlock screen without issue and allow you to re-login to KDE.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Manjaro KDE Plasma working with unstable branch
(available in About System)
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.97.0
Qt Version: 5.15.6

ADDITIONAL INFORMATION

Tested with kernels 5.19.8-1 and 6.0.0rc5-1