[CentOS] new firefox upgrade, then crash

Fri Apr 29 18:11:51 UTC 2016
ken <gebser at mousecar.com>

Earlier today I upgrade firefox, closed the old version, opened the new, 
and first it froze-- displayed a message about a script running and 
asking me if I wanted to stop it; I said no to let it run-- then it 
crashed and disappeared.

# ps -ef|grep firefox
root      3150  4904  0 14:08 pts/2    00:00:00 grep --color=auto firefox

# uname -r

# cat /etc/centos-release
CentOS Linux release 7.2.1511 (Core)