I hope I have the right section for this.
I installed KDE before the much needed How to listed here.
https://endeavouros.com/docs/pacman/how-to-install-desktop-environments-offline-install-users/#kde-plasma
I didn’t have a partial loading desktop, UNTIL I found the setting to fix the way the theme…Arc Dark was affecting dolphin giving it a candy cane effect in the directory.
That thing that solves the candy cane effect was the QT5 Settings in the menu.
Unfortunately after I found that, I was plagued with a partially loading desktop and about the only thing that would work was alt+F2 search menu.
Just follow the section in the above link and goto the section that refers to
And remove qt5ct (tool to configure qt apps in gtk environments)
Thankyou @Bryanpwo for that, idk when you posted that, but this is a specific issue that seems to happen if you don’t do that.
Just saying if it helps anyone 