Unofficial Notion Calendar (Linux desktop)

Electron wrapper for Notion Calendar: minimize to tray, native desktop notifications (via notify-send / libnotify), and persisted window size and position.

Linux only — there are no macOS or Windows builds here; anything outside Linux is untested and unsupported.

Tested environment: Ubuntu 24.04 with KDE Plasma (including correct window icon grouping via StartupWMClass in packaged builds). Other distros or desktops may work but have not been validated.

Fork

This repo (opsmachine/notion-calendar) is a fork of dusansimic/notion-calendar. Thanks to the original author for the app baseline and MIT license.

Upstream is a minimal Linux-friendly wrapper; this fork adds updated dependencies, stricter Electron defaults, tray behavior, and Linux-native notification actions.

Features in this fork

• Tray — Closing the window minimizes to the system tray instead of quitting. Tray menu: show/hide, quit, developer tools. Single-instance: launching again focuses the existing window.
• Native notifications (Linux) — Calendar alerts are not shown with Electron’s built-in Notification API. The main process runs notify-send (from libnotify) so notifications match your desktop environment (e.g. KDE), including critical urgency and action buttons where supported.
  • Click the notification body → focuses the app (freedesktop default action).
  • Join / meeting link → when a URL is detected in the payload, a single Join-style action opens that link in the default browser.
  • Reminder timing (e.g. 10 minutes vs 1 minute before) comes from Source Calendar / per-calendar settings, not from this wrapper.
• Bridging — The page main world and service worker contexts are patched so Notification and ServiceWorkerRegistration.showNotification forward to the main process over validated IPC (preload + dedicated service-worker preload).
• Window state — Last width, height, and position are restored via electron-store.
• Chrome-like user agent — A pinned Chrome-on-Linux user agent is applied (see CHROME_UA in src/main/index.ts) so the embedded site behaves like a normal desktop browser session.
• Packaging — npm run build:linux builds a .deb. electron-builder.yaml also lists rpm/flatpak targets, but the npm script is wired to Debian only right now. Icons and Freedesktop metadata (including StartupWMClass) are set so the app groups correctly in the taskbar and launcher on KDE and similar desktops.
• Developer experience — Application menu (with Alt to reveal the menu bar on Linux when it is hidden), F12 / Ctrl+Shift+I to toggle DevTools, tray entry for DevTools. The main process logs each notification payload and extracted join URL to stdout whenever a notification is dispatched—useful when you run npm run dev or npm start from a terminal.

Requirements

• Linux with a notification server that supports notify-send from libnotify (standard on Ubuntu and KDE Plasma).
• Install if missing, e.g. sudo apt install libnotify-bin.

Security-related hardening

These are defense-in-depth measures; they do not replace a formal audit and do not imply the app is “fully secure.”

Area	Implementation
Renderer	contextIsolation: true, nodeIntegration: false, nodeIntegrationInSubFrames: false, sandbox: true
Navigation	In-window navigation is limited to allowed hostnames (calendar.notion.so, calendar-api.notion.so), matched with URL / hostname checks (not raw string prefixes, so lookalike domains cannot spoof the list). Other URLs open in the system default browser
New windows	Same hostname allowlist as navigation; external targets are not kept as captive Electron windows
IPC	Renderer notification IPC requires the sender frame URL to use an allowed hostname; about:blank / empty senders are rejected. Service-worker IPC checks the worker scope the same way. Payloads are validated and title/body lengths are capped before notify-send runs
Permissions	Session permission handlers only grant notifications; other permission requests are denied
Native notify	notify-send is invoked with execFile (no shell), with bounded arguments

Repository hygiene: .env files, *.pem / *.key, and similar patterns are in .gitignore to reduce the risk of committing secrets or keys by mistake.

• Email / password sign-in — Signing in with email and password in the main calendar page works in typical use.

Known limitations

• OAuth / social sign-in — Third-party login often relies on popups or extra windows to identity providers (e.g. Google). This wrapper’s window and navigation rules treat those flows in ways that do not complete inside the app today, so OAuth-based sign-in may not work.
• Notification appearance — Action styling and colors follow your Plasma / desktop theme, not the Notion web app.

If you need OAuth in-app, it would require a dedicated, reviewed approach (e.g. carefully scoped window.open / redirect handling for provider URLs), not a quick toggle.

Development

npm install
npm run dev

Preview production bundle:

npm start

Linux package (see electron-builder.yaml):

npm run build:linux

License

MIT — see LICENSE.

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Last updated: 2026-04-03 (Europe/Vienna)