NEWS

Mouser: An open source alternative to Logi

I discovered this project because all-of-a-sudden Logi Options Plus software updater started taking 40-60% of my Intel Macbook Pro until I killed the process (of course it restarts). In my searches I ended up at a reddit discussion where I found other people with same issues.I'm a minor contributor to this project but it aims to reduce/eliminate the need to use Logitech proprietary software and telemetry. We could use help if other people are interested.Please check out the github link for more detailed motivations (eliminating telemetry) as a part of this project. Here is link: https://github.com/TomBadash/MouseControl Comments URL: https://news.ycombinator.com/item?id=47368033 Points: 265 # Comments: 78

By Hacker News

• March 13, 2026 at 6:42 PM

Mouser: An open source alternative to Logi Photo: Hacker News

A lightweight, open-source, fully local alternative toLogitech Options+for
remapping every programmable button on theLogitech MX Master 3Smouse.

No telemetry.

No cloud.

No Logitech account required.

The UI shows an interactive diagram of the MX Master 3S.

Click any button's hotspot dot to change its action.

Note:The architecture is designed to be extensible to other Logitech HID++ mice, but only the MX Master 3S is tested.

No install required.Just download, extract, and double-click.

That's it — the app will open and start remapping your mouse buttons immediately.

Tip:To run without a console window, usepythonw.exe main_qml.pyor the.lnkshortcut.

AMouser.lnkshortcut is included.

To create one manually:
To produce a standaloneMouser.exethat anyone can download and run without Python:
The output is indist\Mouser\.

Zip that entire folder and distribute it.

Alow-level Windows mouse hook(SetWindowsHookExWwithWH_MOUSE_LL) runs on a dedicated background thread with its own Win32 message pump.

It intercepts:
Intercepted events are eitherblocked(hook returns 1) and replaced with an action, orpassed throughto the application.

The MX Master 3S gesture button doesn't send standard mouse events.

Mouser uses a 3-tier detection system:
Polls the foreground window every 300ms usingGetForegroundWindow→GetWindowThreadProcessId→ process name.

Handles UWP apps by resolvingApplicationFrameHost.exeto the actual child process.

The central orchestrator.

On app change, it performs alightweight profile switch— clears and re-wires hook callbacks without tearing down the hook thread or HID++ connection.

This avoids the latency and instability of a full hook restart.

Mouser handles mouse power-off/on cycles automatically:
All settings are stored in%APPDATA%\Mouser\config.json(Windows) or~/Library/Application Support/Mouser/config.json(macOS).

The config supports:
The app has two pages accessible from a slim sidebar:
Contributions are welcome!

To get started:
If Mouser saves you from installing Logitech Options+, consider supporting development:
Every bit helps keep the project going — thank you!

This project is licensed under theMIT License.

Mouseris not affiliated with or endorsed by Logitech.

"Logitech", "MX Master", and "Options+" are trademarks of Logitech International S.A.