{
  /*** [SECTION 0500]: SYSTEM ADD-ONS / EXPERIMENTS
       System Add-ons are a method for shipping extensions, considered to be
       built-in features to Firefox, that are hidden from the about:addons UI.
       To view your System Add-ons go to about:support, they are listed under "Firefox Features"

       * Portable: "...\App\Firefox64\browser\features\" (or "App\Firefox\etc" for 32bit)
       * Windows: "...\Program Files\Mozilla\browser\features" (or "Program Files (X86)\etc" for 32bit)
       * Mac: "...\Applications\Firefox\Contents\Resources\browser\features\"
              [NOTE] On Mac you can right-click on the application and select "Show Package Contents"
       * Linux: "/usr/lib/firefox/browser/features" (or similar)

       [1] https://firefox-source-docs.mozilla.org/toolkit/mozapps/extensions/addon-manager/SystemAddons.html
       [2] https://searchfox.org/mozilla-central/source/browser/extensions
  ***/
  /* 0503: disable Normandy/Shield [FF60+]
   * Shield is an telemetry system (including Heartbeat) that can also push and test "recipes"
   * [1] https://wiki.mozilla.org/Firefox/Shield
   * [2] https://github.com/mozilla/normandy ***/
  "app.normandy.enabled" = false;
  "app.normandy.api_url" = "";
  /* 0505: disable System Add-on updates ***/
  "extensions.systemAddon.update.enabled" = false; # [FF62+]
  "extensions.systemAddon.update.url" = "";        # [FF44+]
  /* 0506: disable PingCentre telemetry (used in several System Add-ons) [FF57+]
   * Currently blocked by 'datareporting.healthreport.uploadEnabled' (see 0340) ***/
  "browser.ping-centre.telemetry" = false;
  /* 0515: disable Screenshots ***/
  #   // user_pref("extensions.screenshots.disabled", true); // [FF55+]
  /* 0517: disable Form Autofill
   * [NOTE] Stored data is NOT secure (uses a JSON file)
   * [NOTE] Heuristics controls Form Autofill on forms without @autocomplete attributes
   * [SETTING] Privacy & Security>Forms and Autofill>Autofill addresses
   * [1] https://wiki.mozilla.org/Firefox/Features/Form_Autofill ***/
  "extensions.formautofill.addresses.enabled" = false;      # [FF55+]
  "extensions.formautofill.available" = "off";              # [FF56+]
  "extensions.formautofill.creditCards.available" = false;  # [FF57+]
  "extensions.formautofill.creditCards.enabled" = false;    # [FF56+]
  "extensions.formautofill.heuristics.enabled" = false;     # [FF55+]
  /* 0518: enforce disabling of Web Compatibility Reporter [FF56+]
   * Web Compatibility Reporter adds a "Report Site Issue" button to send data to Mozilla ***/
  "extensions.webcompat-reporter.enabled" = false;  # [DEFAULT: false]
}