User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060505 Minefield/3.0a1 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060505 Minefield/3.0a1 Please take a look at the test case I'm going to attach. Firebug shows that the request was successful, but the callback assigned to onreadystatechange isn't called because of this: Error: [Exception... "Not enough arguments" nsresult: "0x80570001 (NS_ERROR_XPC_NOT_ENOUGH_ARGS)" location: "JS frame :: chrome://firebug/content/firebug.js :: anonymous :: line 628" data: no] Source File: chrome://firebug/content/firebug.js Line: 628 Line 628 is spy.onreadystatechange.handleEvent(); To get this error, you'll need Firebug with "Show XMLHttpRequests" enabled. I see this with Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060505 Minefield/3.0a1 ID:2006050511 [cairo] Working with Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20060504 Minefield/3.0a1 ID:2006050405 [cairo] Regressed by bug 198595? Reproducible: Always

Bugs on Firebug are not mozilla.org bugs. Firebug is an extension that lives outside mozilla.org code. Therefore, this bug is INVALID. I'm cc'ing myself in case you disagree.

How do you know the bug is with Firebug, and not with something in Gecko that Firebug relies on? The fact that an extension is involved doesn't make a bug necessarily invalid.

Especially since there is a regression range corresponding to a gecko change. If Firebug was relying on something broken, we should at least know what before closing the bug as invalid.

Firebug will need to be changed to pass the event object it gets in the callback as an argument to handleEvent.

Yeah, this is invalid. Firebug was using a private unfrozen API, and we changed that API. Please do file a bug on Firebug. Alex, Gavin is right. Generally speaking, if we break an extension it might well be a bug in our code, so just being an extension does not make a bug invalid.