Simple, modern, lightweight & fast web-based email client.
Mobile booting with ~144 KB download (using Brotli) and up to 99% performance grade by Lighthouse.
This is a fork of the much appreciated RainLoop, but with massive changes to be compatible with (mobile) browsers in 2020.
Checkout the source, releases and wiki at GitHub
Here's a short comparison
SnappyMail and RainLoop