Hello,
I've just come across an issue with Flashback in arch. It doesn't seem to work with libgtop 2.30.0. When I tried to log into a Flashback session with libgtop 2.30.0 I simply got a blank grey screen.
I had to downgrade to libgtop 2.28.5 and I had to downgrade metacity to a version built against 2.28.5 to log in successfully. Can anyone else confirm this issue?