User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:50.0) Gecko/20100101 Firefox/50.0 Build ID: 20161104212021 Steps to reproduce: All Macs up to date. Removed Firefox reinstalled with latest and al back versions 50.0 and above REPEATEDLY. Reinstalled Firefox with Clean My Mac 3 to ensure all support files were also removed, then reinstalled all versions of Firefox 50.0 and above 51.01. Reset Mac. Reset/ Refreshed Firefox. Removed ALL add-ons. Started Firefox in safe mode. Temporarily Stopped Bitdefender Anti Virus for Mac. Ran Firefox with and without add-ons. Interestingly after completely refresh install of latest version in Safe Mode with absolutely nothing else installed (fresh) no crash occurs. But without Safe Mode, crashes occurs every 30 seconds. One mac was running OSX Yosemite with Firefox v+50, I upgraded to Sierra and crashes continued. I must use v50.0, else it is unusable on 3 Macs. Actual results: All 3 MACs running Sierra and Yosemite experience constant crashing with any version beyond Firefox 50.0. Last stable version is v50.0. Firefox quits unexpectedly every 30 seconds of less. I have been sending full crash reports many dozens and dozens of times. Expected results: I installed every version of Firefox between v50.0 and 51.01. A macs experience crashes beyond v50.0. This occurs with all 3 Macs so it is not specific to with one mac. WILL FIREFOX CORRECT THIS IN FUTURE SO FIREFOX +50 CAN USE USED and contact me???

Do you have some crash reports (bp-...) in the page about:crashes? If yes, post some links.

One of several crash reports from my iMAC

Another crash report from my iMAC #2

Another crash report from my iMAC #3

Crash report from my MacBook Pro Laptop #1

Another crash report from my MacBookPro Laptop #2

This bug is a duplicate of Bug 1309696.