User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b4) Gecko/2008030317 Firefox/3.0b4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b4) Gecko/2008030317 Firefox/3.0b4 In FF3.0b4rc1 I get this error message: uncaught exception: [Exception... "Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIXPCComponents_Utils.import]" nsresult: "0x80520012 (NS_ERROR_FILE_NOT_FOUND)" location: "JS frame :: chrome://browser/content/browser.js :: DMP_init :: line 7166" data: no]; It does not occur on FF2.0.0.12. It happens every time I restart FF3. The stack that comes into JSD's onError is <top> (0)chrome://firebug/content/errors.js:98-233@99 <bottom> which points to // extends ConsoleObserver observe: function(object) { HERE>> if(typeof(FBTrace) == "undefined") return; /*@explore*/ var context = FirebugContext; Reproducible: Always Steps to Reproduce: 1. 2. 3.

(In reply to comment #0) > location: "JS frame :: > chrome://browser/content/browser.js :: DMP_init :: line 7166" data: no]; Hmm, this is the download manager init stuff, so let's move over to that component. Not sure what would cause the two jsm modules to not exist, though. > It does not occur on FF2.0.0.12. The download manager was rewritten for FF3, and this code in particular was added fairly recently. > It happens every time I restart FF3. Do you only see this with Firebug installed?

See also bug 408412. This sounds like it might be a duplicate of bug 419929 (which is about the addons manager, but it also tries to import DownloadUtils.jsm).

(In reply to comment #1) > > Do you only see this with Firebug installed? > I see it with Firebug + Chromebug, I'm guess the latter is the one that is probing

Hrm - why would it not exist?

It might exist but have a syntax error (again, see bug 408412).

This went away around FF3b5