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 3.10.0-327.10.1.el7.x86_64 # cat /etc/centos-release CentOS Linux release 7.2.1511 (Core)