ShellIconOverlayIdentifiers - why so few?
问题 At this point, everyone knows that there's a limit to the number of ShellIconOverlayIdentifiers (from MSDN): The number of different icon overlay handlers that the system can support is limited by the amount of space available for icon overlays in the system image list. There are currently fifteen slots allotted for icon overlays, some of which are reserved by the system. For this reason, icon overlay handlers should be implemented only if there are no satisfactory alternatives I can