Languagetool.org: auto-detect wrongly selected language

Until now, if you selected a wrong language on languagetool.org you’d get an error message that was not that useful. I’ve now implemented an improvement that lets you choose the correct language with a single click:

Please give it a try (by intentionally selecting a wrong language) and let me know if there are issues.

It does work; it only changes the language things are checked in, not the interface.

Works for me so far, but tbh I’m not exactly a fan of the design. What about a yellow or orange background instead of the red border?

I’ve added an issue so the designer can have a look next time.