I coincidentally stumbled over a
(really) minor inconvenience, and it's probably something, that has been reported somewhere in the 2844 previous posts already, but...
When you're in "General Discussion", and you click on "My Settings", you'll see
(among other stuff) your avatar, and the following text beside it: "
to change, visit My account".
"The words "My account" hide a link
([url=https://www.gog.com/myaccount)https://www.gog.com/myaccount)[/i[/url]].
However: that link doesn't lead you to the page where you can change your avatar
(and other stuff), but to your games shelf, instead.
The correct link, to go to the page where you can change things regarding your account, is:
https://www.gog.com/en/account/settings/personal (alternatively: hover mouse over [your account's name/your nick in the header] --> click on [Orders & settings] --> click on [ACCOUNT AND LOCALE])