Btw, it is lightweight, open source, and not built on Electron.

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Aerion is a new open source desktop email client for Linux (and other platforms) built with Wails and Svelte instead of Electron. It supports multiple accounts, conversation threading, a WYSIWYG composer, contact sync via CardDAV/Google/Microsoft, and works with Gmail, Outlook, Proton Mail, iCloud, and generic IMAP/SMTP. The app holds a CASA Tier 2 security certification and collects no telemetry. A hands-on first look reveals smooth Gmail OAuth setup, blocked remote images by default, and vim-style keyboard shortcuts, but notes issues with no desktop notifications, no configurable sync interval, and a dismissible account-setup dialog with no warning. It is available on Flathub and GitHub as pre-release software.

I Gave Desktop Email Clients Another Shot and This New App Delivered

“No Electron”, but a WebView instead: Wails - basically a Tauri alternative in Go (or Tauri is its alternative in Rust - whatever floats your boat 😉). Lighter than Electron, but still employs much more resources than a classic, native desktop app.
Normally, I wouldn’t even bother saying the above, but with current hardware price hikes, I’m really looking for solutions that are cheap resource-wise. No WebView-, CEF- or Chromium-based apps cut it (for me at least 🙂).

Gmail spyware works good enough for me.
If I wanted to change it I would probably sloppify a web client lol