imgur seems to have this weird and annoying habit of detecting you're browsing from a mobile device even on links direct to the image, and then redirecting you to their site and lowering quality of the image you're looking at. At this point I just don't open imgur links when browsing from my phone.

Imgur has become actively hostile to anyone who browses the mobile website instead of using the app. They've spent years slowly pruning functionality out of the mobile site and just recently announced that in August users won't be able to log into the mobile site at all.