Hello, I am using Thunderbird 52.7.0 64 bit on three operating systems and three partitions, with a shared home directory for private stuff and the Thunderbird mail and settings directory. The normal home folders of the operating systems have a symbolic link to the (hidden) .thunderbird folder in that shared home directory. Last week I installed Ubuntu 18.04, which is now installed besides Ubuntu 16.04 Mate, and ubuntu Media which runs on XFCE, Before I had no problem to open my mails in any of the operating systems. Now suddenly the Ubuntu 18.04 and the Ubuntu Mate, show the accounts I have set up in Thunderbird, but I cannot see any folders or mail. Neither the RSS feeds are showing up. I checked the permissions, and double checked, reset them, and all the operating systems have the same user name and use the same password. When I open Thunderbird as root (sudo Thunderbird from terminal) I can see the mail in the other two operating systems where I as a normal user were not able. But I have read that this naughty behavior can wreck my configuration even more, so it was just a test. Any ideas?