Created attachment 31556 [details]
git libdrm/mesa/ddx with rv790. extraneous transparent boxes under kwin gl are seen to the left of the object and at the bottom right. also visible elsewhere, such as on the active application tabs on the kde taskbar.
Created attachment 31557 [details]
Unreproducible in latest git.
*** Bug 25825 has been marked as a duplicate of this bug. ***