Firefox 30 is out! And excitingly, it now provides column numbers in exception stack traces.
With the column number, we can use source maps to figure out the line of actual code which crashed. This makes debugging much easier in many cases, as you can quickly see what your code was trying to do when it crashed.
As can be seen Firefox comes a pretty close second to Chrome for exception features. Once Firefox 31 is out (estimated July) with access to the error object from [CODE]window.onerror[/CODE] (we were involved with fixing that too) there will be nothing to choose between the two.