Is this related to the forum? That's where you posted - for issues about this forum. If not, tell us which version of Opera you are talking about and we can move your post there - or just repost in the appropriate forum yourself, and mention which version of Opera when you do.
@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.