[zottel]

This was reported before in the forums, and I had the problem myself on a specific site that I unfortunately didn't remember afterwards and couldn't find in the history. On that site, it didn't happen always—even the same page could have scrollbars one time and none later. I never saw this problem on any other site, though, so it seems to be very specific.

So I can only confirm that this bug exists but can't provide any help for reproducing. :-/