Comment 7 for bug 1957948

The new snapd release 2.54.3+20.04.1ubuntu0.2 in focal makes this error message go away for me, but it completely broke my (Plasma) desktop session, because XDG_DATA_DIRS was not set before (making something fill it on start; don't know where that happens), but it now contains only /var/lib/snapd/desktop.
The session start adds some paths, but notably /usr/local/share and /usr/share are missing.

I fixed it for me by wrapping the last lines of /usr/share/fish/vendor_conf.d/snapd.fish in an if:

  12 │ if not set -q XDG_DATA_DIRS
  13 │ if not contains $snap_xdg_path $XDG_DATA_DIRS
  14 │ set XDG_DATA_DIRS $XDG_DATA_DIRS $snap_xdg_path
  15 │ end
  16 │ end