Firefox 40.0.3 instability with Norton Toolbar

I am using Firefox 40.0.3 along with the Norton Toolbar (mainly due to the Identity Safe) on a Windows 8.1 system. I have Norton Internet Security installed with the latest updates (Version 22.5.4.24) Unfortunately, the toolbar causes my firefox to crash several times a day. I have tried uninstalling both Firefox and Norton Internet Security (with the Norton removal tool) and also ran "Wise Registry Cleaner" in between. All these measures did not help.  I posted to the Firefox Forum and looking at the crash report, it appears to be an issue with the Norton Toolbar. Here are some of the more recent rash report ID

bp-b01b5e6d-83d0-44d6-afb7-e661d2151008    08.10.2015    14:39
bp-3290d808-1503-4e47-8383-b08692151008    08.10.2015    12:55
bp-cbf7b076-9e2a-4bd3-ae9e-f3fc82151007    07.10.2015    09:05
bp-209189a6-89f0-4835-8cb8-2634d2151006    06.10.2015    20:11
bp-57bb02a0-6f89-429a-b315-c46d02151006    06.10.2015    18:57
bp-18a4939d-4e88-41cc-aa34-aa9a52151006    06.10.2015    15:42

Is this a known problem?

Should I use Firefox 40.0.0 instead?

 

Thanks for the help