Firefox Extensions

Copy Selection as Markdown copies a page title, URL, and selected text as Markdown through a Firefox add-on.

Yet Another Speed Dial combines a new-tab page and bookmark manager for Chrome, Edge, and Firefox, with site thumbnails and organization features.

Multithreaded Download Manager downloads files using multiple connections to a server, which its listing says may increase download speed.

Bookmarks Organizer finds bookmarks that no longer work and helps users put their saved links in order.

Anori adds customizable new-tab pages to Chrome and Firefox, with widgets for bookmarks, calendar, to-do items, and notes.

Auto-Sort Bookmarks sorts Firefox bookmarks by multiple criteria, with settings for automatic sorting.

Adaptive Tab Bar Colour changes the Firefox theme color to match the appearance of the current website.

Auto Refresh Plus lets users set page refresh intervals and monitor changing web pages in Chrome, Firefox, Edge, and Opera.

Browse OpenSearch and Sherlock plugins that add site-specific search providers to Firefox, Internet Explorer, and Chrome.

Browserling provides live online cross-browser testing, where users can interact with websites in real browsers.

Update Scanner monitors webpages for changes, including sites that do not provide Atom or RSS feeds.

Firefox Scripts provides userChromeJS, autoconfig.js, and extension scripts, with installation instructions for Firefox Developer Edition.

Firefox CSS Hacks collects user stylesheets for changing the appearance of Mozilla Firefox.

Save links, notes, and images with Karakeep, an open-source bookmark manager offering automatic tagging and self-hosting.

Dark Background and Light Text changes webpage colors to show light text on a dark background through a Firefox add-on.

Pagetual automatically joins successive pages for infinite scrolling and supports custom rules across major browsers.

SocialFocus hides selected distracting elements on social media sites in Safari, Chrome, and Firefox.

PWAsForFirefox helps users install, manage, and use Progressive Web Apps in Mozilla Firefox.

Shortkeys lets users customize browser keyboard shortcuts, including navigation, video controls, and JavaScript commands.

SelectON adds a popup of actions for selected text in Chrome and Firefox, including copy, search, conversion, translation, and link actions.

Dark Reader is an open-source MIT-licensed browser extension for Chrome and Firefox that analyzes web pages and generates a dark mode to reduce eyestrain.

New Tab Override lets Firefox users choose which page appears whenever they open a new tab.

The FirefoxCSS Store is a community catalog for discovering and sharing Firefox userChrome.css themes.

fx_cast is a Firefox extension that enables Chromecast support for casting web apps and HTML5 media, according to its project page.