bonkmaykr via tde-users composed on 2024-03-22 15:50 (UTC):
I've got an issue where the layout and mode of my displays resets to the default at every login. This is despite me setting up the monitors in the TDE Control Center, both locally as my user and globally as root, creating an X config using the NVIDIA X Server Settings, and having no such issue previously when I was still using KDE Plasma.
I'm using the latest NVIDIA proprietary drivers on EndeavourOS, with a 1920x1080@60hz display on DP-1 and a 3440x1440@144hz display on DP-2. The ultrawide 1440p display is on the right slightly above the smaller one, but Trinity and TDM both repeatedly place them in the opposite arrangement with the smaller monitor as the default, sitting on the top right corner of the larger one. Both displays default to 60hz at login.
I don't know if I understand your description of where you want what, whether a desktop space expansion, or a partial mirroring. Regardless, install and use arandr to create an xrandr script, or create one manually, that produces the layout you desire. Then put that script in Endeavor's equivalent to /etc/X11/Xsession.d/ in Debian and derivatives so that it will run as your X/TDE session starts. First, reset/undo whatever you have in kcontrol, or the script's effect won't stick.