Is it possible that this is related to this bug?
Very perceptive of you. Yes, I do believe they're related, but I'm not sure how yet. The problem you encountered was occuring when the the
URL to Match for
Default Options (ahem, now called
Defaults by request from taanstafl) was set to nothing. In that twisted case,
nothing really matched
everything. You worked around it by setting the value to
about:config.
The real solution is that
Defaults should not have a
URL to Match and, in fact, I removed that from the RDF for one of the recent releases. I thought that would fix it, but apparently it's still occuring in some cases... like this one.
I'm working on it reproducing it. If anyone can give me steps to do that, it would make fixing it pretty easy and painless.
-Eric