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3.2 Overrides [Common]

Thorin-Oakenpants edited this page Nov 22, 2023 · 30 revisions

🟩 Previous: Overrides

🟥 Summary: Arkenfox v115.1+ makes approx 110 pref changes. Of those, a tiny few cover almost all usability issues

  • Your mileage may vary
  • You can always change your overrides at any time and "undo"/"redo" things
    • ⚠️ except deleted items (such as cookies, history and session restore)
  • See that warning above? Now make sure to read the tiny few items below, because arkenfox deletes items by default

⭐ There is also an interactive version of the user.js at that you can:

  • search, filter, collapse and expand to your heart's content
  • use to lookup items, decide what to override, and troubleshoot


  • 0403: We disable binary checks not in Safe Browsing local lists
    • ⚠️ If you do not understand the consequences, override this


  • We delete all cookies and site data on close
    • There is no need to change any prefs - to keep some cookies and logins, just add site exceptions: either
      • Ctrl+I > Permissions > Cookies > Allow (when on the website in question)
      • ☰ Settings > Privacy & Security > Cookies & Site Data > Manage Exceptions
    • For cross-domain logins, add exceptions for both sites
      • e.g. (site) + (single sign on)
    • ⚠️ Be selective with what cookies you keep, as they also disable partitioning, see bugzilla 1767271


  • 0102: We disable session restore
  • 0810: We disable search & form history
  • 1223: We enforce strict pinning
    • Override if you have issues with antivirus
  • 2811: We delete history (download, form and browsing histories) on close
    • And 2820 for manual sanitizing


  • 4501: We enable RFP 🥇 THE #1 ISSUE and 4504: letterboxing
    • letterboxing is independent of 4501 and is the pref that can creates borders around your webpages
  • 4520: We disable WebGL

Read the next wiki page to decide if you want to keep using RFP. You have options.


Other preferences may cause site breakage, but nothing that can't be fixed. You won't "lose" anything...- it's not the end of the world.

  • Check our override recipes
  • Check already answered issues
  • While not 100% definitive, search for [SETUP in the user.js; e.g.
    • [SETUP-WEB] can cause some websites to break
    • [SETUP-CHROME] changes how Firefox itself behaves (i.e. NOT directly website related)
  • You may also want to add items e.g.
    • 5000s optional

🟩 Next: Overrides [To RFP or Not]