With one of my config changes I found that #Emacs was no longer rendering images when I tried to open an image file in image-mode. After some careful bisecting, the problem turned out to be global-whitespace-mode. I'm not sure why whitespace-mode would be enabled in image-mode buffers, but the fix was easy: (setq whitespace-global-modes '(not image-mode)). This is kind of revolutionary to me because exposing a white- or black-list through one variable like this works pretty great when you have car and cdr functions to process them with. Pretty neat.