Comment 1 for bug 1886113

Thanks for reporting and sorry for not getting back to you earlier. It seems that we have a mismatch between the contents of the XAUTHORITY environment variable (under /home/william) and the actual location of the file on the filesystem (under /Moort/home/william) after resolving symlinks and cleaning the pathname. Are you symlinking an alternate home directory location to /home?

Using an alternate location for home directories can be related to the other problems you've been experiencing. If you're using an alternate location, could you try to bind-mount this alternate location on /home?

Reference: https://forum.snapcraft.io/t/how-can-i-use-snap-when-i-dont-use-home-user/3352/11