IE Tab for Chrome is a free extension that effectively emulates the Internet Explorer rendering engine making it possible for you to visit IE required sites without actually launching IE.
Dark Reader is a free extension for Chrome, Firefox, Edge, and Safari that will make surfing the web easier on the eyes through customizable dark themes.
The Super Simple Highlighter for Chrome extension will allow you to highlight selected blocks of text on a webpage, and restore them on each future visit.
Dark Theme for Google (Chrome, Firefox, Edge, and Opera) allows you to add a dark theme for various Google products like search, contacts, images, and translate.
Screen Shader for Chrome is a freeware extension that provides a soothing orange color to decrease eye strain/fatigue and to satisfy your brain's day/night cycle.
Color Temperature (Change Lux) for Chrome, Firefox, Edge, and Opera can help protect your eyes by adding a warm color to websites allowing you to avoid excessive light.