It's just very inconsistent. It just happens sometimes and I either restart firefox or close and open the tab and it goes away. I can try to take a memory dump

It's just very inconsistent. It just happens sometimes and I either restart firefox or close and open the tab and it goes away. I can try to take a memory dump when that happens. I don't know how useful that might be for you. If I ever get something consistent I will make sure to file a bug. Thanks for all the amazing work though! nothing beats the visual tools and network traces in Firefox.