The pattern is far too regular to be the usual flush related failure, appears to be an off-by-f(x).
Created attachment 40838 [details] aaa|a|a|a||a||a||a
Created attachment 40878 [details] a|a||a Look at the first occurrence of the single bar; notice the missing pixel separator between the two a. At the start of the second bar; notice that the centre of the 'a' is contracted.
http://git.compiz.org/compiz/core/commit/?h=compiz-0.8&id=0f95c41a0aa175ddf7947ba18b01f746c95594a9 https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/635258
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