Imgur (https://imgur.com/) supports HTTPS well if explicitly specified in the browser URL, but does not redirect to HTTPS from HTTP, nor does it redirect you to a HTTPS version of the site upon logging in.
The rule would need to apply to at least these domains, based on what I see in the Firefox Inspector: - imgur.com - s.imgur.com - i.imgur.com - rt.imgur.com There may be others, but I’m not familiar enough with accurate ways to determine all of these.
