You already did help and answered my question.
You showed me the setting in Kspersky that had created the script and why it was there.
I had already resolved the issue before posting my question by simply renaming the file extension of the script from .js to .txt and after restarting my Firefox browser I was no longer blocked from changing the setting in about:config.
Also, I don't publish sensitive information that you are requesting on public message boards.
And you, as a security company representative, shouldn't ask users to do so either.
Sending that data over a private message to one of your reps would be more appropriate.
Thanks for your time.