fmail3

Install command: 
brew install --cask fmail3

Name: FMail3

Unofficial native application for Fastmail

https://fmail3.appmac.fr/

Cask JSON API: /api/cask/fmail3.json

Cask code: fmail3.rb on GitHub

Current version: 1.4.7

Requirements: macOS >= 15

Analytics:

Installs (30 days)
fmail3 29
Installs (90 days)
fmail3 82
Installs (365 days)
fmail3 181