Dark Reader - Reduce eye strain in your browser with this extension that provides a dark theme for browsing.
FireMonkey - Super Lightweight User Script and Style Manager
Monitask - Employee Monitoring Software with Screenshots, Internet, Activity and Time Tracking
Tampermonkey - Greasemonkey compatible script manager.
User JavaScript and CSS - User JavaScript and CSS on any website
Greasemonkey - Customize the way a web page displays or behaves, by using small bits of JavaScript.