Mozilla

Introduction

About Mozilla products and technologies, eg, Firefox or thunderbird

Firefox

Configuration

Profile > about:support > Profile Folder > [Open Folder]

Windows Group Policy:

    HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox\ 

Block third-party module

tl;dr - about:third-party

https://support.mozilla.org/en-US/kb/identify-problems-third-party-modules-firefox-windows

Block McAfee Endpoint Security Web Control

It's injected into extensions.json

The full json node can be removed, but it still loads.

It's loaded by enterprise policy > about:policies

Eg: Extensions > Install C:\Program Files (x86)\McAfee\Endpoint Security\Web Control\e10swcffplg.xpi

The addon can be disabled modifying the group policy:

   HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox\Extensions\Locked\1

from its original value {cb40da56-497a-4add-955d-3377cae4c33b} (eg: altering one hexadecimal digil), restarting Firefox and disabling it from 'Add-on and themes'.