I’m using EndeavourOS with KDE.
The display is correctly oriented when logged in but it doesn’t rotate correctly when I’m logged out.
EDIT: corrected the post. This happens when logged out, locking the screen has it displayed correctly.
If you’re using Wayland, you can go to Settings -> Colors & Themes -> Login Screen (SDDM) and click “Apply Plasma Settings…”
If you’re using X11, it looks like you’ll have to resort to hacky scripts, unfortunately.
Source: https://discuss.kde.org/t/how-to-change-monitor-layout-and-orientation-in-sddm/3377
Is this when the screen is locked or when you’re logged out? Those are two different things and I suspect it’s the latter. That’s probably sddm and I suspect it can be fixed by using Wayland with it. Should be some option in
/etc/sddm.conf
or so.