Under swaywm, the picard window doesn't have it's app_ip property set. One can use the window title to assign the program to a workspace, but this fails for the directory/file dialog window.

A fix would be to add;

set.qApp.setDesktopFileName("MusicBrainz Picard")

As seen here https://github.com/qutebrowser/qutebrowser/pull/4153