Over a period of months, I've noticed heavy use of the hard drive when I shut down browsers. The worst of the worst is MSIE, which can take 10 minutes or so before it stops. Given the amount of time I've observed this, I'm sure it's not due to some other process running on my computer. It happens when I shut browsers down.
During this time, it can be more difficult to reopen the browser or open another browser. Firefox is the worst on this point; often refusing my requests to reopen until at least later in the process. Others can simply delay, but will eventually reopen.
It's become a greater irritation to me lately because I'm trying to do some multi-browser testing. When I successfully start another browser after shutting one down, I'm finding that the new browser session won't do some things properly (HTML5) until the other browser shut-down process has completed.
I hope someone recognizes or can identify the problem and tell me how to deal with it.