@David after your suggestion I tried again and I found finally the problem. The problem is related to the extension "Unity Launcher Integration" v0.1 After disabling the extension I can keep thunderbird on launcher, so I think I should report this to the extension developers. I think you can close the bug
Tks, for your support Giovanni -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/765736 Title: Thunderbird won't stay in launcher and no quicklist -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
