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[rikki cattermole]

Here is his reply from IRC (after you left):

[01:37:57] <opDispatch> hi, only on linux.
[01:38:17] <opDispatch> it's because that depends on the widgetsets.
[01:38:30] <opDispatch> so on linux this is possible thnaks to gtk / Qt
[01:38:52] <opDispatch> but on windows this is not possible because 
native controls (aka WinControls) dont support theming
[01:39:11] <opDispatch> well... in the ancinet times there was uxtheme 
patcher ;)
[01:39:17] <opDispatch> ancient times
[01:39:20] <opDispatch> very ancient