Hello everyone 
I just want to share what my configuration of Firefox is, and you can of course share what’s yours. It will be useful if you want to use this webrowser in /e/ or anywhere else.
1) Preferences
General
Language
Click on “Choose”, and tick the “Request English versions of web pages for enhanced privacy” box.
It helps againt fingerprinting, but it will automatically show every page in English (if available).
Search
Default Search Engine
You should change the default search engine to a more privacy focused one, like Startpage, DuckDuckGo or Qwant for instance.
Search Suggestions
Untick “Provide search suggestions” since it can be used to determine what you are typing.
Privacy & Security
Enhanced Tracking Protection
In order to block a lot of trackers, you should select the “Custom” profil, and tick every box :
-
Cookies : change “Cross-site and social media trackers” to “All third-party cookies”.
This will prevent trackers from putting unique cookies into your webrowser in order to track you. Only the main website will be able to put cookies, which is often necesarry especially if you want to login.
If a website doesn’t work because it needs cookies from another one (which isn’t common), you can temporarily change to a less agressive method. -
Tracking content : change “Only in Private Windows” to “In all windows”.
-
Cryptominers
Prevent the use of your computer as a cryptomining machine, which can happen in the background on some streaming websites for instance. -
Fingerprinters
Prevent the use of some fingerprinting techniques.
History
Tick “Always use private browsing mode”.
Your history won’t be saved and you will be disconnected automatically from every website you have been connected to when Firefox will be closed.
Firefox Data Collection and Use
Untick every box.
Deceptive Content and Dangerous Software Protection
Disable it to prevent a third-party to get informations about what you could download or visit.
2) about:config
When you tap in the navigation bar “about:config”, you will face a warning message. Accept the risks, and you will now be able to change advanced and hidden settings.
Copy paste the following strings in the search bar of the about:config page in order to find the setting line and change it.
(I only mention here settings that can’t be modified in “Preferences”)
-
media.peerconnection.enabled : false
Disable WebRTC connections which can leak you IP address. WebRTC might be useful if you are using a “Web Real-Time Communication” tool that use it. -
privacy.resistFingerprinting : true
It’s a feature made for the Tor Browser, that helps a lot against fingerprinting by changing informations sent in the HTTP header to every website you visit, like the size of the Firefox windows in order to hide your screen size, your Firefox version (it shows Firefox 68.0), your OS (Windows 10 on laptop, Android 6 on mobile).
So don’t be surprised if the automatic download of some software is for Windows instead of another OS (if you are on another OS than Windows). -
privacy.firstparty.isolate : true
Also made for the Tor Browser, it will prevent a website from being able to look at datas (like cookies, cache, and more) stored by another website. -
media.navigator.enabled : false
Prevent website from knowing the status of microphone and camera devices. -
network.dns.disablePrefetch : true
Prevent Firefox from prefetching DNS requests and avoid some privacy and security risks. -
network.prefetch-next : false
Similar to the setting above. -
webgl.disabled : true
Prevent some security risk brig by WebGL. -
dom.event.clipboardevents.enabled : false
Prevent websites from knowing what you copy, past, cut and select on the page. -
browser.cache.offline.enable : false
Prevent website from storing data in case you are offline. -
browser.urlbar.speculativeConnect.enabled : false
Prevent Firefox from starting a connection with a website based on the autocomplete URL. -
dom.battery.enabled : false
Prevent website from knowing the status of your battery. -
network.http.referer.trimmingPolicy : 2
Limit informations provided by the referer header in the HTTP request (which page you come from) to all websites. -
network.http.referer.XOriginPolicy : 2
Send the referer header only if the full hostnames match. -
network.http.referer.XOriginTrimmingPolicy : 2
Only restrict the contents of the referer header attached to cross-origin (different websites) requests. -
browser.sessionstore.max_tabs_undo : 0
Even if Firefox is set not to save history, recently closed tab are saved in Library > History > Recently Closed Tabs.
The number you set will be the number of closed tabs Firefox is allowed to save. -
network.IDN_show_punycode : true
Prevent phishing attack based on the registration of domain in a foreign language. -
browser.sessionstore.privacy_level : 2
Prevent Firefox to store data about contents of forms, scrollbar positions, cookies, and POST data of a session.
3) Add-ons
There are a bunch of add-ons focused on privacy (NoScript, uBlock Origin, Decentraleyes, Cookie AutoDelete, Privacy Badger, uMatrix), so I let you search for the one you like and you need, except for the following one since I think everybody should have it :
HTTPS Everywhere
It will automatically search for an HTTPS version of a website.
The “Encrypt All Sites Eligible” option will automatically show a warning before you reach a website if HTTPS isn’t available.