Hello,
on the website, when entering usernames, such as when sending a permanent message, nickname autocompletion is available. This is a little buggy generally and it can probably be improved, but today I wanted to report a more serious error.

This autocompletion only takes a nickname into account if the user is connected using the same language as your current language of the website.
On the surface, this seems completely fine, however, here is where this goes wrong:
Currently, I am connected in English. Let's imagine that you are connected in Serbian, but you want to send a permanent message to me. If we open the Serbian private messages page](https://qcsalon.net/sr/forum0), and in the recipient field (the first edit box on the page if you are logged in), type Nikola, then tab to the subject field, finish our message, in reality, we will send the message to a completely wrong recipient.
This happened because, silently, the website autocompleted Nikola to Nikolaj (the only available username in Serbian with a match at the moment), and so even though we wrote a valid nickname, this was ignored.
To be exact, it isn't fully silent, if you stay in the recipient edit field you will notice the change of selection, but if you are too fast and just Tab to the subject field as soon as you finish writing, you will not notice this.

Of course, other usernames can reproduce the problem, there are probably tons of patterns available, this was just the real example I encountered with a friend.

If you enter a valid nickname yourself, I don't think the website should make any changes to it. In fact this is my opinion in general, this really shouldn't even be autocompletion, it can just give you suggestions that you may select with arrow keys if you are interested. An alternative is also to take all languages into account, but I'm not sure if that reduces its usefulness a little.
I say this last thing because there are other bugs here too that I haven't been able to reproduce as exactly as this one, but for instance, when trying to view the statistics of a person, and pasting a username, pressing something like CTRL+Home or Home to check what you pasted will result in your input being deleted, but I think this also requires the same situation (viewing statistics of someone from a different language).

Thanks.