I use a lot of extensions to make my life easier, to be more productive or just because they feel right. Here is a list of them along with a small description.
Ublock Origin
Hands down the best content blocker. Apart from being excellent at blocking ads, it allows you to remove annoying elements from websites using its element picker or zapper.
Bitwarden
An open source password manager that provides free cloud storage, is easy to use and is extremely secure as proved by its security audits.
Cookie Autodelete
Open source cookie destroying extension. Similar to Self-Destructing Cookies. Has many features but the most important is that it automatically deletes cookies from closed tabs. This renders cookie popups on pages useless as no cookies can persist between visits.
FastForward
Completely bypasses most link-shortening services and saves a lot of time when browsing.
Bypass Paywalls Clean
Bypasses paywalls on news sites. Requires new permissions now and then as the list expands.
Singlefile
Saves pages into single .html files. Also allows users to annotate pages before saving.
Sideberry
Highly configurable sidebar for easy tab navigation, grouping, categorizing e.t.c. Similar to Tree Style Tab but with many more features.
If you want to use this on firefox, you can hide the top tab row by creating a userchrome.css file and inserting the following lines:
#tabbrowser-tabs {
visibility: collapse !important;
}
/* hides the native tabs */
#TabsToolbar {
visibility: collapse;
}