Logging this against WMF, as I'm not sure if it's a config change, or more likely something in MW
(In reply to comment #2)
/me wonders what happened to the pretty stack traces?
We're getting differences in error handling for some (unknown) reason. It needs dealing with an correcting/reverting
Logged 3 bugs as blocked by this issue due to the naff error information - "Fatal exception of type MWException"