Though this is sadly missing with KDE (the ability, for example, to open up your /usr/share/backgrounds folder and take out one or two naff wallpapers, making dolphin do things you otherwise must do in terminal...
This just didn't work for me. I browsed to /usr/share and selected 'open as root', entered password and ...... NOTHING happened. - May 26 2020
Edit one colour, save, change theme to preview - then go back, try the next one... use Gpick to choose the element of colour from an icon theme you want to use for hilight etc.) - Mar 18 2019
Cinnamon Applets by Laszcz 4 comments