Tooty is an alternative multi-accounts Web client for Mastodon written in Elm by Nicolas Perriault. I've been using it since the beginning on Mastodon and I love it! You should check it out ;-)
You may also be interested in ...
DOMtastic
Small, fast, and modular DOM & Event library for modern browsers.
Native lazy loading for the web
Starting with Chrome 76, you'll be able to use the new loading attribute to lazy-load resources without the need to write custom lazy-loading code or use a separate JavaScript library. Let's dive into the details. Post written by Houssein Djirdeh, Addy Osmani and Mathias Bynens.
Accessibility cheat sheet
Practical approaches to Universal Design for making your website/webapp accessible to everyone.