Mastodon is now on the translation platform Crowdin. So far it seems like a much better interface for translating
You can help by either submitting translations or proofreading existing ones!
@Gargron did you guys considered #weblate as a platform for translations?
@rskikuli It's a closed chapter
Fosstodon is a Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.