I'm trying to change (fix) some file associations on my system. When I change something in system settings, the file ~/.config/mimeapps.list gets updated, but nothing changes with the actual associations. Namely, if I look at the associations in the system settings again, they are back to what they were before. I have checked that there are no other mimeapps.list files in my home directory (I'd read that ~/.local/share/applications/mimeapps.list could cause a conflict).

I actually have no idea where kde/plasma gets its user or system-wide default associations from. The file /usr/share/applications/mimeinfo.cache does not contain the faulty entries I wanted to correct to start with.

I would be grateful if someone could tell me how kde/plasma deals with file associations in terms of files on disk, both system-wide and for individual users.