In the patch I modified widget-image-find to look for @2x images. Can we even modify find-image so it looks for @2x images (as an opt-in feature)? That way Other applications (Magit, gdb-mi, etc) that uses images icons in buffer and fringe could have high-res icons without changing a line of code (assuming they use find-image).

Apart from the font vs image discussion, what about the idea to add @2x images support to Emacs? WDYT? Basically, we add name@2x.xpm images along side the existing name.xpm images. And find-image would prefer those @2x images if, say, image-prefer-hidpi is non-nil.

Yuan