I got information it is a known bug (see comments of Sebastien Bacher), so I remove the file.
-- wrong view of a document https://bugs.launchpad.net/bugs/152597 You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is a bug assignee. -- desktop-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
