Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options) key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?

In safe mode the problem still there. Message of "You have unsubmitted crush report" on screen i see every time after lunch firefox.. In safe mode too...

Start your Computer in safe mode with networking. Then start Firefox. Try Safe websites. Is the problem still there?

Starting The Computer In Safe Mode;
Free Online Encyclopedia

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to Submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

If you can't get Firefox to open, you will have to do this the hard way. https://support.mozilla.org/en-US/kb/mozillacrashreporter Open the file browser / explorer on your computer. Note: You may have to enable Show Hidden Folders / Files. Enter this in the address bar;

Windows: %APPDATA%\Mozilla\Firefox\Crash Reports\submitted Win 7/Vista: C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Crash Reports\submitted Win XP/2000: C:\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Crash Reports\submitted

Mac OS: /Users/<username>/Library/Application Support/Firefox/Crash Reports/submitted Linux: /home/<username>/.mozilla/firefox/Crash Reports/submitted

Copy the last 5-7 Recent File Names in the folder. Post the information in the reply box below.

bp-076d1be1-9f94-471d-9819-531a12160731 31.07.16 13:28 bp-1b04dfc4-84dd-4e41-96e2-1b8902160731 31.07.16 13:28 bp-fda7e097-8d9a-48f4-a9ca-b5ba72160731 31.07.16 13:28 bp-fdd65391-95db-4db2-8622-d65372160731 31.07.16 13:28 bp-22f981cb-8869-4dd0-8526-d440f2160730 30.07.16 16:10 bp-97093547-e105-4141-9953-9d92d2160729 29.07.16 17:04 bp-63ce3fd6-b767-406d-9d94-8e43d2160728 28.07.16 14:57 bp-ba5b3f1a-fd44-44bd-817d-ce70b2160727 27.07.16 23:45 bp-443dd268-de1b-4cac-b523-7f6d52160727 27.07.16 23:42

Signature mozalloc_abort | Abort | NS_DebugBreak | mozilla::ipc::FatalError | mozilla::dom::PContentChild::SendPCrashReporterConstructor

Product Firefox Version 49.0a2 Build ID 20160730004003 Release Channel aurora OS OS X 10.9 OS Version 10.9.5 13F1712 Build Architecture amd64 Build Architecture Info family 6 model 15 stepping 10 | 2

libsystem_kernel.dylib =  ? Word for Mac

I have flagged for more help.

Ok, thanks. I am waiting for your help...