Outlook for Linux

Unofficial Microsoft Outlook client for Linux — a desktop app that wraps Outlook on the web with Linux desktop integration.

✅ System notifications ✅ System tray with unread badge (badge support varies by desktop environment) ✅ Multiple account profiles ✅ WebAuthn / FIDO2 security keys for sign-in ✅ Download manager with KDE JobView and Unity LauncherEntry progress

Note

This is an independent project, not affiliated with Microsoft. Some features are limited by what Outlook on the web exposes.

Relationship to teams-for-linux

This is a fork of IsmaelMartinez/teams-for-linux, re-pointed at Outlook on the web. It is not a rewrite: the upstream tree is kept intact so that new upstream releases can be merged in rather than re-derived. See PORTING.md for how that works and how to pull in a new upstream version.

Upstream's own README is preserved as README.upstream.md, and its documentation under docs/ still describes the Teams build — treat it as reference for the shared plumbing (config, profiles, downloads, tray), not as a description of this app's feature set.

Licensed GPL-3.0-or-later, the same as upstream.

What this build does and does not have

Everything upstream that is not specific to the Teams web app carries over: configuration, multi-account profiles, the tray icon and unread badge, system notifications, the download manager, spell checking, client certificates, WebAuthn, custom CSS, proxy and connection handling.

The Teams-only subsystems are switched off rather than deleted, because they depend on internals (teams2CoreServices) that Outlook has no equivalent of:

Not available	Why
Presence / status, MQTT and Home Assistant integration	Reads the Teams presence service
Calls, meetings, the join-meeting dialog, incoming-call toasts	Teams calling stack
Screen sharing, mic and camera overrides, speaking indicator	Only used during Teams calls
Custom backgrounds, custom stickers	Teams meeting and chat features
Teams theme sync and the in-app settings bridge	Reads Teams' React client preferences
msteams: deep links	This build does not claim the scheme; a real Teams client keeps it

Run from source

npm ci
npm start          # or: npm run start:dev  (adds --no-sandbox)

Build packages

npm run dist:linux:x64        # deb, rpm, tar.gz, AppImage
npm run dist:linux:deb
npm run dist:linux:appimage

Releases

Releases are cut manually from the Actions tab: Release → Run workflow, entering the version. It lints, runs the unit tests, audits dependencies, builds all four x64 package formats and attaches them to a GitHub release (as a draft by default). See PORTING.md for the full procedure.

Configuration

Configuration lives at ~/.config/outlook-for-linux/config.json and uses the upstream schema — see docs/configuration.md.

The one option that defines this fork is the URL it loads:

{
  "app": {
    "title": "Outlook",
    "url": "https://outlook.office.com/mail/",
    "partition": "persist:outlook-4-linux"
  }
}

For a personal Microsoft account, set app.url to https://outlook.live.com/mail/ and add that host to app/helpers/outlookHosts.js.

Pointing app.url back at https://teams.cloud.microsoft restores the full Teams feature set at runtime — the code for it is all still present.

Icons

The icon set is generated, not hand-drawn, so it stays easy to restyle:

python3 scripts/generate-outlook-icons.py

It writes app/assets/icons/ and build/icons/. The mark is a plain envelope; Microsoft's Outlook logo is a trademark and is deliberately not reproduced.