Thank you for the response sfogliatelle. The two you recommend are add-ons for browsers while I wanted the preview to be in windows explorer. Sorry I should have been more careful with words in my request.
QTTabBar has many features, one of which is preview of image files on mouse hover. Though that's the only feature I wanted, ironically I'm liking some of the other features, so I'm keeping QTTabBar and my problem is solved