>>39899467not true, actually. imgur filenames are 6 characters with mixed casing and numbers, whereas reddit filenames are distinct in being about twice that (lol not counting for the autism) and the letters only being lower cased. I think reddit started natively hosting images which is why those filenames are always able to be traced back to that god-awful site.
after a certain amount of time you recognize the filenaming schemes of most sites, tbdesu