STR: 1. Start a debug build from this afternoon or later. (fresh profile optional but not required) ACTUAL RESULTS: Among the first few lines of output is 4 consecutive instances of: { "WARNING: Serializing document without system principal: file nsXULPrototypeDocument.cpp line 424" } ... followed by 2 more instances, after some other terminalspew goes by (for a total of 6) This warning was just added today, here: http://hg.mozilla.org/mozilla-central/rev/eaa69ae330ab#l7.12 as part of bug 592943 (and the comment above the warning says that this is "worrisome"...)

Would be good to change the warning to include the URI. ;)

It turns out the warning was just wrong and we were warning when the document *had* a system principal instead of when it doesn't. This bug was resolved by the backout, and shouldn't come back since I have a fix for the warning in the original bug. I do have a patch to include the URI, but the warning doesn't appear anymore so I don't care so much about pushing for it.