This thread is a complement/companion to the sticky "Detecting leaks and checking for browser fingerprint" above: Once you have seen your browser is leaking so many things, and is so easily fingerprintable, you may want to do something against that.
Here are some possible methods. I tried to be as reasonably complete as possible relative of my knowledge, but being exhaustive is obviously not possible. Feel free to discuss what I wrote, and to give your own tricks an methods.
1) General antifingrerprinting and spoofing (of which UserAgent, screen size, Time&Zone, language, media device and fonts spoofing, keyboard fingerprint fighting...):
Chameleon
Privacy Possum
Trace
(I do prefer Chameleon)
2) Specific :
CanvasBloker (Canvas, Audio, ClientRects, window.name protection, screen size...)
Smart Referer (spoofing/forging referer!)
Privacy-Oriented Origin Policy "Prevent Firefox from sending Origin headers when they are least likely to be necessary, to protect your privacy". See Ghacks article too.
Location Guard Hide/fake your geolocation from websites. Either use a spoofed fixed location, or obfuscate your real geolocation with addition of an adjustable random noise. Remember nevertheless that even without any addon or specific configuration, your geolocation is transmitted to a browsed web site only if you explicitly allow it.
3) Antitracking
a) General
Privacy Badger
DuckDuckGo Privacy Essentials
Ghostery., But it's complicated: Ghostery was formerly owned by Evidon, a company that collects and provides data to advertising companies... Now owned by Cliqz, itself owned by Mozilla and Hubert Burda Media. Probably best to not opt-in "sharing extension usage" and to opt out "Participing in A/B tests".
b) Etags "Prevents Firefox from storing entity tags by removing ETag response headers unconditionally and without exceptions" (Chameleon do that too).
ETag Stoppa
c) Cookies etc
See 4)
c) email
Trocker
d) Isolation
See 5)
e) URLs sanitization
See 6)
f) Google specific
Google Container "Prevent Google from tracking you around the web. The Google Container extension helps you take control and isolate your web activity from Google". Regularly updated.
Google Container - with Integrations A fork of the former. "Additional google domains in this plugin include: Youtube, google services / apps, google ad domains, google utility domains, typo domains (probably not used for cookies, but just-in-case), other Alphabet companies, more google developer domains.
Also an initial list of 3rd party integration apps was added (draw.io, atlassian, etc). Some of these will work without explicitly adding the to the Google Container, but many do not, an a more complete list is convenient, if not prudent". Not updated since 18 months.
Google search link fix "Prevents Google and Yandex search pages from modifying search result links when you click them. This is useful when copying links but it also helps privacy by preventing the search engines from recording your clicks". The dev is V. Palant. Relatively recently updated.
Don't track me Google "Removes the annoying link-conversion at Google Search / maps ". Not updated since 2 years, but seem still working.
Remove Cookie for Google Account Chooser "Automatically to avoid(disable) remain your account information after sign-out". Not updated since 3 years.
g) Redirections
See 7)
4) Addons fighting cookies and all (IndexedDB, LocalStorage, Plugin Data, Service Workers, and browser cache)
Cookie AutoDelete
Forget Me Not - Forget cookies & other data
Site Bleacher
5) Isolation
Temporary Containers "Open tabs, websites, and links in automatically managed disposable containers". And as stated here on Arkenfox: : "Achieve almost everything First Party Isolation (FPI) does without breaking cross-domain logins. And (with or without FPI), in a hardened TC setup, this can even isolate repeat visits to the same domain, which FPI alone cannot".
Container proxy "Allows Firefox user assign different proxies to be used in different containers".
First Party Isolation (see 4))
6) URL sanitization
ClearURLs Efficient and very rarely breacks site.
Neat URL But ClearURLs is more regularly updated.
7) Redirections bypassing
a) General
Clean Links "Protects your private life (and accelerates some pages loading), by automatically detecting and skipping redirect pages, that track you on your way to the link you really wanted.
CleanLinks differs from a number of other add-ons that do parameter removal (such as Neat URL), skip redirects (such as Skip Redirect), or both (such as ClearUrls), as it automatically detects embedded URLs in the links of redirect pages".
Powerful with customizable rules but breaks more pages than ClearURLs and in rare occasions you have to disable the addon in order some page be correctly displayed.
Skip Redirect "Extract the final url from the intermediary url and goes there straight away if successful".
b) AMP (Google/Bing) specific
Amplifier AMP/Canonical switcher It automatically redirects AMP (Accelerated Mobile Page, which are pages served by Google or Bing) to their normal HTML version, and let you the choice to go to the AMP version when/if you want it.
Redirect AMP to HTML "Automatically redirects AMP pages to the regular web page variant".
c) Links shorteners skipping
Universal Bypass Efficiently does what it is supposed to do. Regularly updated. See the FAQ too.
8) Addons decreasing your browser's entropy by setting up Tor's Uplift (possible replacement by FF about:config preferences):
Toggle Resist Fingerprinting
Resist Fingerprinting (see Chameleon too)
First Party Isolation "Enables the First Party isolation pref.
Clicking the Fishbowl icon temporarily disables it (see Chameleon too).
9) Addons decreasing your entropy by blocking scripts and/or some APIs or features
LibreMatrix (replacement of uMatrix, abandoned)
uBlock Origin (with "I am an advanced user" ticked in Settings).
Noscript
Csp Blockler Block certain web resources types, responses headers, frame resources, and features to improve security, privacy and performance
ScriptSafe (unfortunately abandoned)
WebAPI Blocker Not update since 1 year.
PolicyControl abandoned, but still very usable.
WebAPI Manager (abandoned)
10) Local Resource Delivering
LocalCDN It's a fork of Decentraleyes. But I find it now more complete (more cdn supported) and more often updated than decentraleyes. Moreover, with each update, LocalCdn comes with the necessary rules to be set in your uBlock/uMatrix profile in order LocalCDN can work.
Decentraleyes. Remains very good for its purpose, although IMO LocalCdn is now a little better.
11) Headers Modifications
Header Editor (need to be a bit skilled for correct usage.
12) Punctual browser data deletion
Nuke Private Data Optionally delete Cookies, Cache, Download History, Browsing History, IndexedDB, LocalStorage, Plugin Data, Saved Passwords, Saved Forms, Server-bound Certificates, Service Workers.
ZBeacon Transmitter As a reward for the service you are rendering to others in installing this addon, you get the following punctual data deletion feature: Cache ("with better method than the one used by eFF"), Cookies, Download History, Form data, Browsing history, Indexed DB (storage), Local Storage, Plugin Data, Passwords, Server Bound Certificates, Service Workers, Last opened tab, window.name object
13) Web browsing and web searches obfuscation
OpenBubble "Mimics your online browsing behaviour and looks at topics that you may not be interested in to confuse trackers and advertising firms".
Ad Nauseam Block most ads and randomly click on some of them. See Dev FAQ on Github too. Interesting case study paper here
TrackMeNot. Same devs than Ad Nauseam. Obfuscates web searches "by issuing randomized queries to common search-engines". Interesting but hated by Google. You will probably end with having to solve captchas every time you really want to really use Google.
Mystique-FF "produces background traffic while you are normally surfing the web, obscuring your real user profile by opening websites at random". Abandoned, but still working.
14) Addons fighting some vulnerabilities
Don't touch my tabs! (Noopener)
CSS Exfil Protection (Chameleon do that too).
NoEval - Disable Eval(). See here or here for more explanations. Bur NoEval beaks many sites.
15) Direct modifications of FF configuration preferences:
Arkenfox userjs (formerly Ghacks userjs). Very smart and depth, regularly updated (each time a nex FF version is realeased) by skilled & knowledgeable people. Recommended to read the wiki too.
BetterFox, with subsections FastFox, SecureFox, PeskyFox, SmoothFox. Updated every month/couple of month
i2pFox But no update since 2 years.
See too Firefox Hardening, but except Ghack userjs (now Arkenfox), the links here seem outdated.
16) Appendix: Comparison between browsers concerning privacy:
Spyware Watchdog Article Catalog (needs probably a little update, eg concerning Brave). Epic Browser not considered.
RestotrePrivacy/browsers
vox.com
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