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I've been dealing with this problem for a while but I don't quite know how to describe it. If I have desktop effects turn on, sometimes when I scroll an application up or down, artifacts and ghosting may appear. This doesn't seem to happen with desktop effects turned off. (I tried disabling lanczos and blur filters but it doesn't help, desktop effects have to be turned off).
What happens is that when I'm scrolling up or down in an application (Firefox, Open Office writer, etc) it may distort and show part of what should be below on top of what should be above, or may scrunch things down.
This is hard to explain so here is a screenshot:
http://img545.imageshack.us/img545/2012/snapshot1m.png
I'm hoping to fix this, it's really annoying but I've not had time to pursue this until now. I tried the new Mesa 7.9 from testing but that doesn't seem to fix it.
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