A fast, native Windows workspace for your conversations.
The messenger app Windows deserved all along.
Stop juggling sluggish browser tabs and Electron memory hogs. Nuntius brings Messenger and Locket into one lightweight, native WinUI 3 workspace with separate accounts, floating desktop chat bubbles and a quiet way to read without sending “Seen”.
Built for the way you actually chat on a PC.
01
Browser tab fatigue
Three Messenger accounts in Chrome eat gigabytes of RAM, bury notifications, and vanish the moment you clean up your tabs.
02
The pressure of “Seen”
Opening a message marks it seen right away, so you feel you have to reply now, even in the middle of deep work.
03
No real chat heads on desktop
Phones have had chat heads for years. Windows never got an always-on-top version that stays out of the way until you need it.
04
Friends and work in different places
Work chats live in Messenger, close-friend photos live in Locket on your phone. Switching means switching devices.
Everything a desktop messenger should have been.
Multi-account isolation
Multiple accounts, separate profiles, zero session leakage.
Run personal Messenger, work Messenger and Locket side by side. Each Messenger account gets its own WebView2 profile with separate cookies, storage and permissions. Switching is one click, and every account keeps delivering notifications in the background.
Better Unseen & read-only mode
No “Seen” indicators. No pressure.
Better Unseen keeps chats unread on the sender’s side while you read, yet you still see when they have read yours. Need to go fully quiet? Read-only mode stops messages, read receipts, typing indicators and reactions from leaving Nuntius, for every account, with one switch.
Floating chat bubbles
Chat heads, built natively for Windows.
New messages appear as small, draggable heads that snap to the edge of your screen while you game, code or write. Click one to open the conversation beside it, reply right away, and press Escape to fold it back.
Message stack
Draft in bursts. Send in order.
Type your thoughts quickly in the top-bar stack, pressing Enter after each one, review them together, then hit Send all to deliver them one by one, oldest first. No more half-finished messages sent too early.
Native WinUI 3 polish
Built for Windows, not wrapped in a browser shell.
Nuntius runs on the Windows App SDK and .NET 8 with a Mica backdrop and light, dark or system theme. Your chat list appears instantly from an encrypted local cache, the window hides to the tray, and the taskbar badge counts unread messages across every account. Ctrl+K searches, Ctrl+1…9 jumps between chats.
How it works
A native shell around the services you already use, with your data kept on your PC.
- Native frontend
- C# and WinUI 3 on the Windows App SDK, targeting .NET 8.
- Account sandboxing
- Microsoft WebView2 with a separate profile for each Messenger account: its own cookies, storage and permissions.
- Locket client
- A native Firestore gRPC listen stream with adaptive REST polling as a fallback. Only the refresh token is kept, in Windows Credential Manager; your password never is.
- Local by design
- Cookies stay in WebView2’s protected profile, the startup cache is encrypted with DPAPI for your Windows user, and cookies and message text are never written to logs. No Dunori server sits between you and your chats.
Nuntius vs. the usual options
| Nuntius | Browser tabs | Electron wrappers | |
|---|---|---|---|
| Native Windows interface | |||
| Isolated sessions per account | Separate browser profiles | Usually one account | |
| Desktop chat heads | |||
| Read without sending “Seen” | Some | ||
| Messenger and Locket in one app | |||
| What runs per app | Shared system WebView2 | Full browser, one tab per account | A bundled Chromium per app |
System requirements
- Windows 10 version 1809 or later, or Windows 11
- x64
- Microsoft Edge WebView2 Runtime (included with Windows 11)
Nuntius is an independent app. It is not affiliated with, endorsed by or sponsored by Meta or Locket. Messenger and Locket are trademarks of their owners. Using them through Nuntius is subject to their terms.
All your conversations. One quiet, native window.