Mail Checker for Proton Mail

Read, write and manage Proton Mail without opening a tab. Attachments, calendar RSVP, notifications, multi-account.

Mail Checker for Proton Mail *BETA* — access your encrypted inbox directly from the toolbar. Features: * Multi-account support with per-account customization (labels, colors, reorder) * Proton AI writing assistant (Scribe) support in the reply and compose editors * Read, reply, forward, and compose emails with attachments * Rich text editor with formatting toolbar * End-to-end encryption for Proton-to-Proton messages * OpenPGP attachment decryption — click to open in a new tab or download * HTML, plain text, and raw email view modes * Calendar invite detection with one-click RSVP (Yes/Maybe/No) * Two-factor authentication: TOTP and FIDO2/WebAuthn security keys * Mailbox-password / two-password account support * Verification code detection with customizable regex patterns (premium) * Desktop notifications with custom sound, volume, click actions, and preview-text toggle * Custom toolbar badge color * Do Not Disturb mode and message snooze (1h, 3h, tomorrow, next week) * Three UI themes (Classic, Modern, Material) with Light/Dark/Auto color schemes * Adjustable popup size, display density, and pop-out detachable window * Custom CSS injection * 28 European languages * Settings sync across devices via Firefox account * Settings export and import (JSON) * Mailto: handler registration * Credentials encrypted at rest (AES-256-GCM); SRP login (password never leaves your device) Quick Actions: Mark read/unread, archive, delete, delete permanently, star, label, move to folder, snooze, report spam/phishing, view headers / message details — all from the popup. Drag-to-reorder and show/hide individual actions. Compose & behavior options: Default compose / reply format (HTML or plain text), open compose in popup or Proton web, image-attachment mode (inline / attach / both), auto-mark-read on actions, auto-advance to next message, 12/24-hour time, sender display format, configurable polling interval, "Send & Archive" toggle, draft auto-save, contact autocomplete, spellcheck. Privacy: No data collection. All API calls go directly to Proton Mail servers. Website https://apps.olausson.de/mail_checker_for_proton/