It's possible that due to changes in http-on-modify-request, in Firefox 19, the apocalypse is coming.
Trac: Summary: Firefox: Error: wouldMatch is not defined to Firefox 19: Error: wouldMatch is not defined Priority: major to blocker Cc: N/Ato mikeperry
I take it back. The apocalypse is not coming; this is a stupid bug I introduced by the fix for #7491 (moved). That patch won't do it, I think wouldMatch is actually the wrong thing to be calling.