Desktop environment switcher in Gnome

This is a very general question: how did the Cinnamon and KDE desktop environments end up as choices under the “cog” icon on the Gnome login screen?

Did they come to be because of a software package that I installed from one of those DE’s?

If I were to say, switch from Gnome to KDE on login, and continue to configure KDE Plasma and use it, would I damage the Gnome DE I have been using for 6 months?

I’ve read the wiki, and most of the posts in the old forum regarding multiple DE’s, and still don’t know what is safe. I don’t think that I would want to do a reinstall or add a second user account to try a different DE.

Thanks for taking a look at this newbie question.

Yes that’s likely: some applications usually shipped with a DE are actually “part of it”, and thus require the associated core packages to work.

AFAIK the issues are usually related to MIME types and Qt/GTK+ theming, because the configuration files are the same across DEs.
Anyway there’s a reason to avoid switching between DEs with a single user.

You could also try them from a LiveUSB or in a VM.

Thanks for your reply. If I added a second user, how would I access the first users files? Would I have a permissions problem at the onset, or later down the road if I were to switch back? I have to me a fairly complex (but stable) configuration now, with sveral external drives, local and cloud backups, and a Vbox host running Win10 to reach my photo printer.

Not sure if it’s worth the disruption for a trial run. Maybe the best thing is to run the KDE on my Macbook under a VM, and see if I like it.