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
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: