vv221: I can’t reproduce it: avatars on the forum are served through HTTP (unencrypted), but on the account page everything is delivered through SSL encryption, including images.
I use HTTPS-Everywhere (on Iceweasel/Firefox) with a custom rule to enforce HTTPS on www.gog.com, but nothing about images.gog.com, so I don’t think the use of this plug-in is relevant here.
Here's an interesting find. I've reinstated the secure connection for the forum, and how the threads and pages open is a mixed bag. And not only between different threads.
See the attached screenshots for this very thread - on one page the secure connection is broken, yet on another it's not.
Isn't this (at least) an indication that avatars are served in a non-consistent way?