I'm using Cinnamon on a Devuan ASCII system. I'm trying to have Gnome MPV open my .avi files rather than Dragon Player - like I've already done with .mp4 and .mkv files, using the "Open With | Other Application..." dialog of the Nemo file manager. However, for .avi, pressing "Set as Default" keeps Dragon Player as the default, and only changes the order of recommended apps on the list. Playing files manually in Gnome MPV - works fine.
Why is this happening? How can I fix this and make Gnome MPV my default player for .avi files?