Comment 0 for bug 1604478

X-based snaps doesn't work on some distros with KDE5 since the XAUTHORITY env variable points to `/tmp/xauth-${UID}-${DISPLAY/:/_}` that is not usable inside a snap since `/tmp/` is remounted (see kdeinit5).

You can launch the snap (tested on ArchLinux) using the old ~/.Xauthority file:
XAUTHORITY=~/.Xauthority /snap/bin/vlc

If you don't have an updated `~/.Xauthority` just do `cp /tmp/xauth-${UID}-${DISPLAY/:/_} ~/.Xauthority`