From the Bug report cited in your Crash Report. https://bugzilla.mozilla.org/show_bug.cgi?id=1196494#c13 "After I've set html5.offmainthread = false and layers.offmainthreadcomposition.enabled = false, there were no more crashes."

To access those hidden prefs. Type about:config in the URL bar and hit Enter.

(Please don't comment in that Bug report unless you can provide a patch to fix the problem. Posted merely as a reference to a potential fix for you.) https://bugzilla.mozilla.org/page.cgi?id=etiquette.html

Try to set gfx.xrender.enabled to false on the about:config page or possibly toggle its current value.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

• http://kb.mozillazine.org/about:config