At first Instead of my SDDM I would just see an after image of what was last displayed on screen. But if I typed in my password and pressed enter, it would let me in just fine. Then after following some suggestions from users in r/Kubuntu I’ve made a bit of progress. Now when I boot up my computer instead of the SDDM being invisible, it now doesn’t load at all, from there I switch to tty3 then back to tty2 and then log in through the terminal. After that I run startplasma-wayland and then I have access to my desktop. The post where all this went down - https://www.reddit.com/r/Kubuntu/comments/1nvreuo/sddm_not_rendering/
Does anyone know a fix? I would like to be able to see my login screen.
Here’s my specs in case that would help - https://i.imgur.com/XtC43zw.png
And here’s my journalctl output after booting and launching plasma - https://pastebin.com/nnGsWebd
The issue is I have no idea what any of these errors mean. I’m pretty new to desktop Linux so I’ve just been researching the errors one by one but so far, no dice.
Show us! The journalctl output was too restricted, we need to see all of it - at least for the significant timeframe.
Alr here’s all of it. Sorry that took so long. https://drive.google.com/file/d/1bocHEulCDEKUIradHJPTxwI84ZDJcuX9
Not downloading and reading 181MB of logs. You probably used
journalctl
without any qualifiers, right?What we want is
Compose a journalctl command that takes these aspects into account, i.e.:
Also see:
Assuming 1. and 2. are in effect, you can also try this:
journalctl --boot --since "2025-10-15 8:18:00" --until "2025-10-15 8:21:00" --no-tail > log.log
https://drive.google.com/file/d/1syk9Okhq7qA3TLMxNpO-35JmmKFKWIaW
systemctl status -n999 sddm
https://pastebin.com/mF9h0x9e
Hope I did this right.
Neither output shows the string “Failed to read display number from pipe”.
Why?
FWIW, the journal snippet shows a mostly healthy KDE session has started, no errors.
It’s up to you to provide some context now.
Here is a video I recorded of what it looks like to log into my conputer from boot.
https://drive.google.com/file/d/1xX0xYuefGoGZ1ddW5fOG6GPkUThfvE6B/
I genuinely don’t know how to describe this since I don’t entirely understand what is actually going on here.
I see. That’s why it doesn’t show up as an error, presuming you got the instructions from my previous post correct (that the problem actually occured in the timeframe given) - sddm is apparently oblivious to the problem.
Searching “kubuntu sddm blank screen” gives some relevant-looking forum posts; I found these to be good reading:
https://bbs.archlinux.org/viewtopic.php?id=226363 => content of /etc/sddm.conf please
https://www.kubuntuforums.net/forum/newbie-support/help-the-new-guy/68489-sddm-black-screen-but-working-somewhat
They should give you some idea where to go from here.
Since this topic has been going on for a while, to no avail, I will lecture you now: