I've been running 1.0pre against a XULRunner built off of mozilla-central.  I noticed that pasting data
to conkeror from the clipboard resulted in a SEGV.  Poking around, I discovered:

https://bugzilla.mozilla.org/show_bug.cgi?id=769440

In short, in order to support private browsing, nsITransferable objects are now required to be
initialized after being created.  I've attached a patch against the current git tree which fixes the SEGV.

I should clarify and say that I'm running a debugging build of XULRunner.  The SEGV happens for debug
builds because of a MOZ_ASSERT which is designed to catch bugs during the debug process rather than make
browsers crash in the field.  (I'm guessing that manipulating the clipboard was considered something
"internal" rather than external.)  Since conkeror touches these objects, it should DTRT with them.

(Downgrading from urgent.)