Spoofs User-Agent strings of your browser with a new one globally, randomly or per hostname
Send the page you are currently viewing to your mobile device. QR codes are generated instantly in browser and never leave your computer. Implemented with WebExtensions API and compatible with Firefox 57+.
This add-on renders standalone images on a transparent background, so you can see the image in all its glory!
Quickly and easily switch between popular user-agent strings.
'Classic Toolbar Buttons' add-on restores old toolbar button ui (known from Fx 4-7s small view, Fx 4-12s large view & Tb 5-14) for current Firefox, Thunderbird and Seamonkey versions. Beta builds on versions page!
View source code of Firefox add-ons and Chrome extensions (crx/nex/xpi) from addons.mozilla.org, the Chrome Webstore and elsewhere.
Add-on to display GitHub code in tree format
Cookie-Editor lets you efficiently create, edit and delete a cookie for the current tab. Perfect for developing, quickly testing or even manually managing your cookies for your privacy. Also supports Firefox for Android.
RusVPN - Free VPN Service
Enables the resolving of Dot-BIT domains by Namecoin. Also .emc, .coin, .lib and .bazar domains by EmerCoin. Redirecting of NXT aliases.