My personal guides.

How I configure my Firefox

I do not agree with a lot of the default settings used in Firefox. I tweak it using various methods to customize it to my preference and machine.

Custom user.js

I made a custom user.js file that can be found in my repository. It can be added to any firefox profile. Some settings may need to be tweaked depending on your machine or usage. I will outline those settings in the repository README. This user.js was made from the arkenfox user.js.

Applying the user.js file

  1. Download my user.js file (Right click > Save Page As…).
  2. In the URL bar type “about:profiles”.
  3. For the profile you want to use (or default) click “Open Folder” in the Root Directory section.
  4. With the folder open, close Firefox, then paste the user.js you downloaded into the folder.

Custom policies.json (optional)

Enterprise policies are a way of enforcing browser behaviour in an enterprise environment, but can be used by users to do the same. Unlike group policies, policies.json is cross-platform. I have made my own, just like the user.js file, this one can also be found in my repository.

WARNING: These policies are enforced and are usually not modifiable within Firefox. Make sure you go through the file and learn what it does before you use it!

Applying the policies.json file

  1. Download my policies.json (Right click > Save Page As…).
  2. Follow instructions for your platform (this is best done if Firefox was never launched, at least on the profile you use):
  • Microsoft Windows: create a directory called “distribution” where the firefox.exe file is located and place the file “policies.json” there.
  • Apple macOS: create a directory called “distribution” in and place the file “policies.json” there.
  • Linux: create a directory called “distribution” in the directory where Firefox is located and place the file “policies.json” there.


You can enable the new DNS over HTTPS in settings, if it’s not enabled by default.

  1. Click the menu button (3 vertical lines in the top-right) and go to Options.
  2. Scroll all the way down to Network Settings and click the “Settings…” button.
  3. Scroll down and find “Enable DNS over HTTPS”.
  4. Click OK.

WARNING: Default DNS provider is Cloudflare, if you do not trust Cloudflare, use the following link to learn how to change the DNS provider: Application level DNS

WARNING: Using Application-level DNS methods like this one will bypass your local DNS resolver. Pi-hole and similar blockers will not work!

Extensions I use

There is a set of extensions that I install everywhere, including on Firefox mobile. A very good read about what extensions are good, secure and worth using is in Arkenfox’s wiki in the Extensions section.

  • uBlock Origin - Wide spectrum blocker. Many tweakable options.
    Custom lists I use:
  • Bitwarden - A secure, FOSS password manager with cloud sync. I install it on all my devices.
  • ClearURLs Strip URLs of tracking parameters.
  • xBrowserSync - Secure syncing of bookmarks across devices. No sign up. Adds a search bar for browsing all bookmarks. Very convenient.
  • Firemonkey - Light, open source user-script and user-style manager.
  • Terms of Service; Didn’t Read - Displays ratings for domain’s terms & privacy policies, as well as any notable comments from users.
  • DownThemAll - Mass downloader. Can help with finding a way to download some assets without using inspector.
  • SponsorBlock - Easily skip YouTube video sponsors.
  • Web Archives - View archived and cached versions of web pages on 10+ search engines.
  • Firefox Multi-Account Containers - Firefox Multi-Account Containers lets you keep parts of your online life separated into color-coded tabs that preserve your privacy.
  • Skip Redirect - Some web pages use intermediary pages before redirecting to a final page. This add-on tries to extract the final url from the intermediary url and goes there straight away if successful. Less break prone compared to some other alternatives.
  • Search by Image - A powerful reverse image search tool, with support for various search engines, such as Google, Bing, Yandex, Baidu and TinEye.
    • Warning: Skip Redirect breaks this extension. Disable Skip Redirect during its use or add “/searchbyimage” and “/search” to the No-skip-urls-list in the Skip Redirect settings (the latter will make Skip Redirect less effective and is hence not recommended).