I tend to have a couple dozen tabs (in multiple instances) of Firefox running at any given time. But I’ve noticed (at least in Windows) that sometimes the program will start to saturate the CPU, and take forever to reload a site, or even to switch from one tab to another. When I shut down the program, the CPU usage goes from a hundred percent to a few percent. But when I reload it, with all previous tabs restored, it shoots back up to a hundred. I suspect that it’s just one of the tabs that’s causing the problem, but the Windows task manager can’t provide any insight, because it’s happening inside the application.
It would be really nice if the Firefox folks would put in a diagnostic tool that would tell which open tab, or tabs, was causing the problem, so that one could just close that one without having to kill the whole program. It’s really made it almost unusable until I can figure out which one it is. Or just start over, but keeping them open is my way of bookmarking items for later blogging.