Gnome session cannot run snap apps - ? - with NFS mounted home dirs

[lejeczek]

Hi guys.

This is my first foray into Ubuntu world - hopefully can 
change into a long lasting adventure - and have already come 
across strange behavior.
I cannot say if it's only Ubuntu, perhaps other distros 
also, but a user whose home dir is nfs-mounted logged in and 
wanted to start Firefox (which is by default snapped, I 
think) then... Firefox will not start.
Actually nothing happens, no GUI warnings nor errors, but in 
terminal:
...
$ which firefox
/snap/bin/firefox
$ firefox
cannot open path of the current working directory: 
Permission denied

I have not done a through investigation yet and hoping 
people here can comment & advise.
I come from SELinux world - could this be Apparmor thing here?

many thanks, L