CornerExtent is expressed as a percent of the length of each side; the corner will begin at this percentage length. For example, a value of 100 will result in no corner, whereas a value of 50 will appear circular. Values outside the range of 50-100 will produce unusual shapes.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2