WebExtension topic
Universal standard for creating browser extensions.
Working through a W3C charter group, Mozilla has partnered with Microsoft and Opera to define a browser extension API that works across multiple browsers.
There is currently a preliminary specification that matches what Google has implemented in Chrome so that extensions written to the specification could potentially work on Chrome, Edge, Opera and Firefox.
chikamichi
Command pallet for the browser. Enables fuzzy search for histories, tabs and bookmarks.
osm-smart-menu
An OpenStreetMap webextension for Firefox and Chrome
amp2html
WebExtension for automatically redirecting Accelerated Mobile Pages (AMP) to the canonical HTML page.
alfred-firefoxtabswitch
An Alfred workflow for quickly switching between Firefox tabs
radical
Element (Riot Web) unofficially bundled as Firefox Add-on
radical-native
Extending Element (Riot Web) with native capabilities
accept-language-per-site
Firefox extension to change Accept-Language for different sites.
ff2mpv
A Firefox/Chrome add-on for playing URLs in mpv.
refined-wikipedia
Enforces the mobile web version of Wikipedia and improves its interface
languageswitch
Language Switch Add-on for Firefox