Bug 476563

Hi, thank you for your bug report!

Have you configured your system to automatically sleep/suspend instead of just locking? Sometimes computers have issues with waking up from suspend/sleep.

Do you also encounter this issue when you manually lock the screen? Just select lock, don't select sleep or suspend.

Created attachment 163028 [details]
Energy Saving - profile

> Have you configured your system to automatically sleep/suspend instead of just locking? 
I didn't.
For sure this is not result of suspending. In my profile of Energy Saving is set "Do nothing" in case of suspending (check attached screenshot). I use daily profile "On AC Power". In moment of black screen I can see mouse cursor which I can move.

> Do you also encounter this issue when you manually lock the screen?
I don't. Just pressed key shortcut, and got lock screen which I could unlock.

(In reply to Piotr Mierzwinski from comment #3)
> > Do you also encounter this issue when you manually lock the screen?
> I don't. Just pressed key shortcut, and got lock screen which I could unlock.

Does this also happen when you manually lock, and wait for 60 seconds for the screen to turn off? (I see from your settings your screen turns off after 60 seconds when locked).

(In reply to fanzhuyifan from comment #4)
> (In reply to Piotr Mierzwinski from comment #3)
> > > Do you also encounter this issue when you manually lock the screen?
> > I don't. Just pressed key shortcut, and got lock screen which I could unlock.
> 
> Does this also happen when you manually lock, and wait for 60 seconds for
> the screen to turn off? (I see from your settings your screen turns off
> after 60 seconds when locked).

When I did this my monitor just hang (no any reaction on power button) to unhung it I needed to plug off power cord and plug it again. In result I saw lock screen and could login normally.

I didn't mention this earlier, by my monitor is connected via USB Type C hub by HDMI connector.
My monitor is NEC EA275WMi (the buttons it has are touch sensitive, not physical so this maybe was the cause I could not turn it off).

And I remind. The issue happens in normal session. After waiting time my screen getting black (and turns off). I was moving my mouse instantly to back to session. In result by fraction of a second I can see background of lock screen, after that the screen turns black with visible mouse cursor, which I can move.

BTW. I tried back to normal session by switching to text terminal, killing sddm and go to TTY with sddm again. I got login screen, but in result of login my monitor just hung (details I described this on begin this post).

This behavior I observe since couple weeks (lock screen I tested today). Let me know if you need any additional information about my hardware or configuration of KDE/Plasma.

BTW. I reported similar issue: 475632 where monitor turns off in moment of login to plasma session.

> Alt+F2 doesn't work
It's actually Alt+Ctrl+F3. Hit that, and then hit Alt+Ctrl+F2 again. Does that resolve it?

Is this with a laptop, or a desktop?

(In reply to Nate Graham from comment #6)
> > Alt+F2 doesn't work
> It's actually Alt+Ctrl+F3. Hit that, and then hit Alt+Ctrl+F2 again. Does
> that resolve it?
> 
> Is this with a laptop, or a desktop?

Such switching doesn't help, even restart of sddm (sudo killall sddm).
Workaround is to plug off power cord and plug it again.

I work with laptop.

BTW. Today, after yesterday update, I observed similar issue, but instead of black screen I got screen with lockscreen background (and with watch). Of course there was mouse cursor. Switching didn't help, even restart of sddm didn't. Plugging off cord from monitor and plug in again didn't help. I needed to restart my PC.

Thanks. Does this happen when you lock the screen by closing the lid and then later re-opening it? If so, does it stop happening if you lock the screen with Meta+L but don't close the laptop lid?

(In reply to Nate Graham from comment #9)
> Thanks. Does this happen when you lock the screen by closing the lid and
> then later re-opening it? If so, does it stop happening if you lock the
> screen with Meta+L but don't close the laptop lid?

I work with closed lid. I open it very few time (check out my Display Configuration). I configured bios in my Dell laptop such that after I plug power cord it turns on. Issue usually happens because my inactivity. 
So do you want I would did such test - would open lid and close it?

As "fanzhuyifan@gmail.com" asked me at  2023-11-05 06:10:26 CET 
> Do you also encounter this issue when you manually lock the screen?
I don't. Just pressed key shortcut, and got lock screen which I could unlock.

Created attachment 163280 [details]
Display Configuration

Can you try again with today's updates/packages? A bunch of lock screen fixes went in two days ago, and there have been some screen-related improvements as well.

(In reply to Nate Graham from comment #12)
> Can you try again with today's updates/packages? A bunch of lock screen
> fixes went in two days ago, and there have been some screen-related
> improvements as well.

Seems issue fixed.
This time I didn't get black screen with mouse cursor only I saw background of screenlocker. After I move mouse cursor before 5 seconds have passed I'm able to back to my desktop. When I wait more I get field where I can enter password to unlock the screen.
Therefore all is fine.
Thank you

Phew!