how to migrate from kde to gnome without full reinstall
Uninstall Plasma, install Gnome
sudo pacman -Rnsc plasma
sudo pacman -S gnome
I don’t know if your data will be preserved, but I assume so.
If you don’t want to take any risks, backup your home directory.
these settings are in your home folder and these data stay always untouched until you do something with it
The topic opener can therefore switch from KDE to Gnome without losing data.