It is possible this is NOT a Mozilla bug. Read my analysis of Apple Bug Reporter script: Infinite loop in Apple Bug Reporter script
The following image shows the problem (in Firefox).
The following image shows the correct result (from Safari).
The next link lets you see the Page Source for the Apple Bug Reporer page:Firefox.html.txt
Finally, the link for the Sample taken by Activty Monitor while the loop occurred:Sample.Firefox.txt
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