HWCursor doesn't help for me, because that is standard (I'm always using HWCursor.).
Yesterday I also had a time of several hours, where this garbage didn't appear, so you can't really be sure unless it didn't appear for let's say 2 days or so.
BTW, this is not a problem of some software (KDE, Firefox or whatever).
This is a problem of the driver, because if you make a screenshot, it is not there.