[SOLVED] login screen hangs on KDE when not logging in fast enough.

chillecharlie · 2025-10-02 12:31:27

Hi guys,

I edited this post since i managed to fix it and this might help others.

The problem
When turning on the computer with Arch and KDE Plasma 6 while using the Breeze sddm theme (the default) if you do not login after a couple minutes the login prompt disappears.
When this happens you basically only see the background image and there is no way to login anymore.
The only solutions are rebooting the system or restarting sddm.

The cause
I was searching for a solution and found a post saying that there was a bug in the Breeze theme that should have already been fixed.

The solution
I changed the sddm theme to another Plasma 6 theme (McMojave by VinceLiuice) and the problem is solved.
Note: when changing the sddm theme make sure you use a theme that supports the right plasma version or you will end up with a black screen.
If this happens you can change it back by editing /etc/sddm.conf.d/kde_settings.conf and changing the theme back to breeze.

Last edited by chillecharlie (2025-10-03 06:01:59)

seth · 2025-10-02 13:43:01

Please use [code][/code] tags. Edit your post in this regard.

dmesg won't help if the problem is w/ output config and login failures, please post your complete system journal for the boot:

sudo journalctl -b | curl -F 'file=@-' 0x0.st

Also what does this mean:

Typing in the password and pressing enter also wont work.

https://bbs.archlinux.org/viewtopic.php?id=57855

https://wiki.archlinux.org/title/KDE#Un … lution_set ?

chillecharlie · 2025-10-02 14:11:28

edit:
Here i explained the issue i though i had, but it was something completely different.
I thought it had something to do with turning on the tv after powering on the laptop.
What i failed to notice since i use a very long hdmi cable and dont really use the laptop display while i sit far away from the laptop is what actually happened on the laptop display.

Last edited by chillecharlie (2025-10-03 05:54:46)

chillecharlie · 2025-10-02 14:31:15

edit
I thought i fixed it and explained what i did here even though it seemed to have nothing to do with it.
Turns out it had nothing to do with it so removed this not to confuse others.

Last edited by chillecharlie (2025-10-03 06:04:26)

seth · 2025-10-02 14:45:51

When i turn on the laptop and let it start up all the way while the tv is off it displays the background on my laptop display, just the image nothing else.
If i then turn on the tv i expect the sddm login screen on the tv display, but it isnt there the display is completely black and the laptop display still shows the background only.

That depends on the display server, X11 will add and enable outputs present when it starts but not automatically afterwards. SDDM could provide that (like kscreen, x-on-resize etc. etpp) but idk whether it does.
You'd typically start some tool w/ SDDM - the alternative would be to configure the X11 server/driver to explicitly consider outputs to be enabled.

"sudo journalctl -b | curl -F 'file=@-' 0x0.st" got you a URL to share, there's no need to copy around the internet.

Oct 02 15:23:26 arch sddm-greeter-qt6[951]: Adding view for "DP-2" QRect(0,0 1920x1200)
Oct 02 15:23:26 arch sddm-greeter-qt6[951]: Adding view for "HDMI-0" QRect(1920,0 3840x2160)

in this case those two outputs were there from the start.

chillecharlie · 2025-10-03 04:25:52

I managed to reproduce it with my morning routine, but this time i watched closely at what happened.
The laptop booted normally and for a couple of minutes the login prompt actually was right there on the laptop display itself!
Then after a couple of minutes the login prompt disappeared and only the background remained visible.
After that i can no longer login.

edit:
After figuring out the above, i found a solution quite fast and edited the thread to remove noise and explain the problem and the solution on the top post.

Last edited by chillecharlie (2025-10-03 05:58:12)

Arch Linux

#1 2025-10-02 12:31:27

[SOLVED] login screen hangs on KDE when not logging in fast enough.

#2 2025-10-02 13:43:01

Re: [SOLVED] login screen hangs on KDE when not logging in fast enough.

#3 2025-10-02 14:11:28

Re: [SOLVED] login screen hangs on KDE when not logging in fast enough.

#4 2025-10-02 14:31:15

Re: [SOLVED] login screen hangs on KDE when not logging in fast enough.

#5 2025-10-02 14:45:51

Re: [SOLVED] login screen hangs on KDE when not logging in fast enough.

#6 2025-10-03 04:25:52

Re: [SOLVED] login screen hangs on KDE when not logging in fast enough.

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