I have Request Policy on Firefox, which blocks external files from a website unless it has been whitelisted. Randomly today, I noticed it was blocking a user's profile image. Apparently, this person has their image hosted on Facebook.
How exactly does someone link to an external site for their photo? When I go to change my image, I only get the option to upload a photo (which itself is a relatively new feature) or use Gravatar.
Is it Gravatar that is linking to the image externally? I haven't used the Gravatar image ever since uploading my own, so I don't remember how it sotred/linked images.
Or is the "upload photo from web" option actually just linking instead of copying to the StackExchange network?