The essential one: Ublock Origin of course; surfing the web without it is next to impossible today.
-A bit less essential but very helpful:
HTTPS Everywhere: forces the browser to connect to secure pages anyway.
Privacy Badger: by the EFF. Blocks trackers.
uMatrix: NoScript on steroids. Allows to turn off parts of the web page with deep granularity (filter by domain and type of data). Needs "training", not for new users, don't install on granma's PC.
Duck Duck Go Privacy Essentials: Blocks trackers and other things.
-Then among the useful albeit not essential:
DownThemAll: to quickly download files (docs, images, pdfs etc) from sites.
The essential one: Ublock Origin of course; surfing the web without it is next to impossible today.
-A bit less essential but very helpful:
HTTPS Everywhere: forces the browser to connect to secure pages anyway.
Privacy Badger: by the EFF. Blocks trackers.
uMatrix: NoScript on steroids. Allows to turn off parts of the web page with deep granularity (filter by domain and type of data). Needs "training", not for new users, don't install on granma's PC.
Duck Duck Go Privacy Essentials: Blocks trackers and other things.
-Then among the useful albeit not essential:
DownThemAll: to quickly download files (docs, images, pdfs etc) from sites.
FeedBro: Feed reader. Featureful RSS, Atom, RDF Reader.
Nitter Redirect: Redirects automatically Twitter links to Nitter, a Twitter front end that respects the users privacy.
Redirect AMP to HTML: Redirects Google AMP pages to their original ones.
Bypass Paywalls: to bypass many news sites paywalls.
StartPage.com: Redirects searches to StartPage.com, which essentially is to Google what DuckDuckGo is to Bing.
Livemarks: Restores RSS live bookmark support on Firefox after it was removed from Mozilla.
Search By Image: a reverse image search addon which supports various search engines.