This issue just started today. Every time I open a new window, Firefox becomes completely unresponsive for a few seconds. Basically, the new window opens up, but then there's a delay between me clicking on a bookmark, the address bar, the menu or anything else until it actually happens in any Firefox window I have open. I've tried restarting Firefox, restarting my computer, resetting my settings under Help->Troubleshooting Information, and upgrading from 26 to 27 Beta, but no luck. I'd appreciate any assistance I can get to resolve this. Thanks.