Appears broken on MediaWiki >= 1.42

[clarfonthey]

Poking through the debugger, it appears to fail on this like:

JWB.page = response.query.pages[response.query.pageids[0]];

Since the page it's being queried is a redirect, it appears to only offer a redirects key instead of a pages key. I'm not sure why or how the API changed here, but this does seem like a legitimate bug.

Ran into this since Miraheze recently updated to 1.42, and JWB no longer works on there for me.