It turns out that all FreeFlarum forums have been automatically updated to 1.1.0. We've originally wanted to update during next weekend, but it seems that when all extensions were updated (by composer update), it also updated Flarum to the new version.
I've removed automatic extension updating because of this. Luckily, it wasn't a big update and everything behaves as it should. But, if your forum experiences any issues, please let us know and we'll look into it. AFAIK, one forum had issues with FoF Best Answer, which I've told them to report (since the error was generic, and they know more about their forum setup than we do). I assume that it is a minor issue and that this extension will shortly update to 1.1.0, so I won't remove it
Edit: Also fixed navigation not visible for desktop or mobile on https://freeflarum.com
