Installed Kopia on Fedora 44 Kinoite (fully updated), and on 43 Plasma and 44 Plasma (fully updated). Kopia icon is in system tray, however, the Kopia UI does not open. Right click to select repository, UI does not open. Installed Kopia on Fedora 44 Xfce and works fine the UI displays.
Kopia was installed on Plasma and Kinoite using Discover (and tried install script on Kopia web site on Plasma, same issue).
If any suggestions please let me know.
I think that Xfce uses X11 for the display manager and all the others you mentioned use wayland. Do you know whether Kopia is intended to run on wayland or if it is only able to run on X11?
A quick search online to determine with which DE it is supported seems to indicate that the gui depends on electron which I think is X11 only, though there is some indication it may be able to run the gui in limited fashion on wayland. Apparently the cli interface works on wayland with no problems.
Since this is clearly a 3rd party app, most support will need to come from the source.
Electron apps in general work fine on Wayland desktops, via XWayland.
But I don’t know if Kopia is doing something different than a “normal” Electron app.
Also tried Kopia on Fedora Silverblue (Gnome) and the UI never displays. Thanks for all the information, will keep investigating.