Created attachment 2086 fix markup The "reset to defaults" displays a message that has a markup, but XfceMessageDialog escapes the markups, thus it should be removed. See attached patch.
May be a non-bug as I'm actually running an not-up-to-date svn revision. I will let you know about it...
Ok, I verified on a recent revision, it's a yes-bug.
*** This bug has been marked as a duplicate of bug 4785 ***