[Conkeror] Conkeror incompatibility with xulrunner 1.9b4pre

[Jeremy Maitin-Shepard]

Mozilla recently released a new xulrunner snapshot, 1.9b4pre.  I don't
know if this snapshot fixes anything, but it does introduce a very
serious problem:

It completely breaks the JavaScript multi-threading support, which is
needed for launching external programs from Conkeror, due to
deficiencies in the API for launching external programs.  As a result,
Conkeror will hang or possibly worse while the external program is
running.  I recommend that everyone stick with xulrunner 1.9b3pre until
this problem is corrected, or the use of JavaScript multi-threading is
eliminated from Conkeror (dependent on a better process launching
facility).

-- 
Jeremy Maitin-Shepard