We have about 40 Opensuse Clients in our Network and switched lately from Opensuse 13.1 to Opensuse Leap 42.2. At the moment we are using the LTS Version of Plasma5: 5.8.6 but it also happened with older versions. When a user is logged in for quite a while it is not more possible to start any application graphically. When I try to start in a console, we always get this error equal which application (firefox, libreoffice, dolphin, konsole, ...) : testuser@test:~> thunderbird & [2] 3580 testuser@test:~> No protocol specified Error: cannot open display: :0 [2]+ Exit 1 thunderbird After relogin of the user everything works fine again. Not very practicable during the working day ;-) It is really an annoying bug for the users. We are using a NFS Fileserver (Debian Jessie) and for Single Sign on Authentication a LDAP Server (Debian Jessie). Unfortunately I can`t find anything in the logs like a crash or something. Please tell me what information you need to debug this behavior. Thanks!
Your Xauthority file is being deleted. See the linked bug report. It's not a Plasma problem. *** This bug has been marked as a duplicate of bug 370608 ***