Metacity using the Bluecurve-classic theme:
As the window gets/loses focus, the "v" arrow sign on the top-left
button of the window moves one pixel horizontally.
Created attachment 98313 [details]
The first part of the patch does nothing, it is just to show which two values
have to be the same.
Thanks. I commited this to CVS, and it'll be in the next release of
Fixed in 0.94.