Henry I mean Chrome only warns saying "hey the site is encrypted but there's 3rd party content that's not".
Some browsers are not as kind; they just remove the https indicator, making it seem as if the site is not secure.
... But I generally prefer to enforce a "no hotlinking" policy, and explain to my users why I don't want them doing it. Because it's the site, not the users, that will end up with a bad rep for bandwidth theft.
Kulga Is there something you can do to mitigate this or were you just making a general statement?
Inserting a proxy would allow the images to be served over https, so the site's https indicator is unaffected.