In th wiki is this section :The following settings have only effect for the “new-style” browser window:
ButtonColorFrom
ButtonColorTo
ButtonHotColorFrom
ButtonHotColorTo
ButtonSelectedColorFrom
ButtonSelectedColorTo
ButtonSeparatorColor
SplitterColorFrom
SplitterColorTo
DividerColorFrom
DividerColorTo
HeaderColorFrom
HeaderColorTo
FrameColor
ToolPanelColorFrom
ToolPanelColorTo
ToolPanelHeaderColorFrom
ToolPanelHeaderColorTo
But there is no explanation how and where to use it