I have reproduced this issue on 17.10. After logging out of a wayland session, the socket is left behind.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to libreoffice in Ubuntu. https://bugs.launchpad.net/bugs/1749484 Title: [snap] fail to launch after logging in to a wayland session then back into an X11 session Status in libreoffice package in Ubuntu: Confirmed Bug description: My default session is "Ubuntu" (/usr/share/xsessions/ubuntu.desktop). If I log out, then log in to "Ubuntu on Wayland", then out again and in to "Ubuntu" again (so I'm back to my initial session), the libreoffice snap fails to start: osomon@bribon:~$ /snap/bin/libreoffice /snap/libreoffice/49/lib/libreoffice/program/soffice.bin X11 error: Can't open display: Set DISPLAY environment variable, use -display option or check permissions of your X-Server (See "man X" resp. "man xhost" for details) osomon@bribon:~$ env | grep DISPLAY DISPLAY=:0 Rebooting my machine "fixes" the issue. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/1749484/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : firstname.lastname@example.org Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp