@leocg It would enhance the user-friendliness of the website. Wordpress Zoho Forums are a few other examples which ensure this Accessibility feature is honored.
You should either copy and paste a selection or post a screenshot - while I only read 2 languages I can identify all the major ones on sight.
But the first thing to check is Setting > Languages. Second thing - some websites will second-guess if you are using the VPN, the most common guess seems to be Ukrainian.
As I'm sure you noticed, new users posts must be approved by a moderator. Possibly that's why your comment didn't work - at the time you weren't a forum member.
Yes you are right every post is moderated on a high quality blog like this one.
The button was temporarily removed as the option to upload your own avatars was not permitted on this forum anyway, for security reasons (so the button was misleading and promising something that did not work).
On the help page - https://forums.opera.com/help - the very first item explains that Gravatar is the source of user pictures here. Which is what majority of people use, I think.
[UPDATE]
The ability to upload your own avatars was re-enabled.
Post in the correct forum.
Be clear and concise when describing the problem. Be specific and remember to include important details, such as the exact error message or address of the site you're having trouble with.