It seems all javascript-related language strings are missing on the site (mark all as read, search, quote selected text, etc).

Yes, looks like it's all JS-strings.

Changed Status to Duplicate

 

It seems all javascript-related language strings are missing on the site (mark all as read, search, quote selected text, etc).

It seems to be the same issue I commented on my board. The lang bits are there in jslang (other users reported it too) but they’re not being used somehow.