When I do a Google Images search, the results are fuzzy, even if I enlarge with ctrl++. How can I get a higher resolution preview? Perhaps a browser extension or a search parameter?
Image previews (called thumbnails) you see in Google Image search are no bigger than 200×200px. This results in fuzziness you experience when you zoom in your view. It's like you would watch a video file of resolution 426×240 (240p) on 200" TV (eg. not a good idea).
You should go for an extension called Hover Zoom+ which is able to show you full an image behind the thumbnail and all of that without even single click - just point your cursor on the image and wait 0.5 seconds (wait time can be lowered in settings)