Greasemonkey - Customize the way a web page displays or behaves, by using small bits of JavaScript.
Sass - Syntatically Awesome Style Sheets
Random User-Agent - Automatically change the user agent after specified period of time to a randomly selected one, thus...
PostCSS - Increase code readability. Add vendor prefixes to CSS rules using values from Can I Use. Autoprefixer will use the data based on current browser popularity and property support to apply prefixes for you.
Tampermonkey - Greasemonkey compatible script manager.
Stylus - EXPRESSIVE, DYNAMIC, ROBUST CSS