User Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:16.0) Gecko/20100101 Firefox/16.0 Build ID: 20121011002034 Steps to reproduce: We are seeing a bizarre, but consistent problem in the JavaScript engine in Firefox 16, where a simple variable value assignment is not working correctly. This is a critical problem, but we have no idea what's causing it. Actual results: We have simple code that reads: option.itemId = resultSet.elements[i].itemId; In Firebug, we see that the right side of this expression is a uuid string like "_1DAaMIVZEd-H05quvknDew", but after stepping over this line the left side is assigned a value with a url prepended like "https://localhost:9443/jazz/_1DAaMIVZEd-H05quvknDew". The URL that's getting added to the front of the value is the URL of the site the page comes from. The attached screenshot shows the problem. You can see the value on the right side which is assigned to "option.itemId" and you can see that after stepping over this line the value is different. I've redacted parts of the code that aren't relevant. This problem is 100% reproducible on Firefox 16.

Jared, see https://bugzilla.mozilla.org/show_bug.cgi?id=802548#c5 for an explanation of what's going on here.