One of my organization's web servers (Ubuntu with Apache & PHP) recently got knocked out of service by a sudden burst of 400ish repeated requests in 20 seconds from a logged-in user. It looks accidental, rather than a deliberate attack.
Here are two representative lines from the log (slightly munged for privacy):
48.151.62.342 - - [17/Oct/2012:15:06:20 -0400] "GET /blahblah/view.php?id=12345 HTTP/1.1" 200 2238 "http://blahblah.org/" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:16.0) Gecko/20100101 Firefox/16.0"
48.151.62.342 - - [17/Oct/2012:15:06:20 -0400] "GET /blahblah/view.php?id=12345 HTTP/1.1" 200 4331 "http://blahblah.org/" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:16.0) Gecko/20100101 Firefox/16.0"
Obviously we are fixing the server config so dumb stuff like that doesn't kill it. But I'm curious: what might cause Firefox to do that?