Remove a lang from the mastodon web interface.
On chrome, install the Tampermonkey extension here : https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo?hl=fr
On firefox, is should be here : https://addons.mozilla.org/fr/firefox/addon/tampermonkey/
https://github.com/arthurlacoste/mastodon-lang-remover/raw/master/mastodonLangRemover.user.js
By default, the script remove Japanese, Chinese, French, German, Spanish... basically any toots that have include characters outside of a-z, A-Z and special characters such as !@#$%^&*():?]/
The script uses regex to look for specific character ranges and hides toots that match.