JMAP Webmail – modern webmail client for Stalwart

JMAP Webmail is a self-hosted browser email client built primarily for Stalwart Mail Server.

Instead of relying on IMAP for mailbox access, it communicates using JMAP, a modern protocol designed for synchronising email and related data efficiently. The application combines mail, contacts and calendar functionality in a responsive interface and supports both individual accounts and shared mail environments. It is built with Next.js and TypeScript.

This is free and open source software.

Key Features

• Read, compose, reply, forward, archive, delete, search and organise email through JMAP.
• Provides threaded conversations with inline expansion and virtual scrolling for large message lists.
• Offers a unified inbox across personal, shared and group accounts.
• Supports sending through shared identities while retaining clear account context.
• Uses JMAP push events for new-message notifications, unread counts and other real-time updates.
• Includes address-book management with server synchronisation, contact groups, autocomplete and vCard import and export.
• Provides month, week, day and agenda calendar views with event creation, recurrence, reminders and invitation handling.
• Includes server-side mail filtering through JMAP Sieve with both a visual rule builder and raw Sieve editor.
• Supports multiple sender identities, signatures and sub-addressing.
• Blocks external message content by default and sanitizes HTML email before rendering.
• Displays SPF, DKIM and DMARC authentication information.
• Supports TOTP two-factor authentication and optional OAuth/OIDC single sign-on.
• Offers keyboard shortcuts, drag-and-drop organisation, batch actions, configurable interface density and dark and light themes.

Website: github.com/root-fr/jmap-webmail
Support:
Developer: Matthieu Malvache
License: MIT License

JMAP Webmail is written in TypeScript. Learn TypeScript with our recommended free books and free tutorials.

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