Hi! I have Manjaro KDE installed at the moment at I would like to switch to XFCE. I would like to delete KDE and install XFCE, without losing user account and home partition. I’d do that with a new installation but at the moment I don’t have time for that. What is the correct way to do that?
Read the wiki articles on installing extra desktops.
When you understand them - and have installed the necessary packagtes - you only have to logout - select xfce in the display manager and login.
Switching between desktops using the same toolkit is not very hard - but as KDE builds on a completely different toolset and a completely different approach to theming etc. - there will be implications which can be hard to predict and hard to troubleshoot.
I understand that you want a clean system but the best way to do that is to make a backup and reinstall. But unused software only takes place in your drive why can’t you wait and do that reinstall when you have more time?
TBH don’t waste your time in trying to remove KDE after a install of xfce DE.
I would recommend you a re-install after backing up all valuable files.
Installing a second DE is easy, removing it is the hard and not-supported task and so far nobody will present you all the single steps you have to perform - it’s simply not a recommend approach.