Automatically guess a topic language so posters don't have to select one

A common barrier to posting: not beinb allowed to post without choosing a language. Is there a simple library we can use to detect and guess the language of a post? Then on posting, it could remind the author that it guessed X, or highlight the guess somehow, rather than adding a step. [just happened to me a third time when trying to post this note!]

@Sj thank you for this suggestion.

Turns out there was a setting about forcing language selection or not. After changing the setting to not require manual selection of language, now users can post a new topic without selecting a language, and then the language will be automatically detected.

If the language is not detected or is detected wrongly, then users can edit the tags manually. Users can still add the language tag(s) manually when posting a new topic if they wish.

Can you test this in the #site-feedback:sandbox and verify that it works as expected, please?