Privacy Policy

Effective date: 2026-04-04 · Last updated: 2026-04-04

Quasar has no backend servers and does not collect, transmit, or store any personal data on our end. Everything described in this policy lives exclusively on your local device.

This Privacy Policy explains what information Quasar handles, how it is used, and what third-party services are involved when you use the Application. By using Quasar you agree to the practices described here.

1. Information We Do Not Collect

Quasar does not operate any servers that receive or store user data. We do not collect:

Your Microsoft account credentials or passwords
Your Minecraft username, UUID, or profile information
Authentication or refresh tokens
Your installed instances, mods, worlds, or settings
Usage analytics, telemetry, or diagnostic data
Your IP address or any network identifiers

2. Information Stored Locally on Your Device

Quasar stores the following data in your local application data directory. This data never leaves your machine unless you explicitly export it:

Microsoft authentication tokens — OAuth access and refresh tokens used to authenticate with Xbox Live and the Minecraft Services API. Stored locally and never transmitted to Quasar's servers.
Account profiles — Your Minecraft username, UUID, and skin URL, cached locally to display in the launcher interface.
Instance configurations — Names, mod loader types and versions, Java settings, and installed content metadata for each instance you create.
Saved skins — Skin image files you choose to save in the skin library.
Launcher preferences — Settings such as memory allocation, JVM arguments, and UI preferences.

3. Microsoft Authentication

To sign in to your Minecraft account, Quasar uses Microsoft's OAuth 2.0 authorization code flow:

You are redirected to Microsoft's login page in your browser. Your password is entered directly on Microsoft's servers — Quasar never sees it.
Upon successful login, Microsoft issues an authorization code which Quasar exchanges for an access token and refresh token.
These tokens are used solely to authenticate with Xbox Live and the Minecraft Services API to verify your game license and retrieve your profile.
Quasar requests only the minimum OAuth scopes required (XboxLive.signin, offline_access).

Microsoft's handling of your data is governed by the Microsoft Privacy Statement.

4. Third-Party Network Requests

Quasar makes network requests directly from your device to the following services. We do not proxy, log, or intercept these requests:

Microsoft / Xbox Live / Minecraft Services API — account authentication and Minecraft profile retrieval.
Modrinth API — browsing and downloading mods, shaders, resource packs, and datapacks. Requests include your search terms and the Minecraft version and loader of your active instance.
Adoptium (Eclipse Temurin) — downloading managed Java runtimes when you request them.
Quasar update server — periodically checking for launcher updates. This request includes your current launcher version and platform.

Each service's own privacy policy governs how they handle these requests.

5. Discord Rich Presence

When enabled, Quasar sends your current activity (e.g. "Playing [instance name]") to the Discord client on your local machine via Discord's local IPC socket. This data is handled entirely by Discord under their Privacy Policy. Rich Presence can be disabled at any time in Launcher Settings and is on by default.

6. Launcher Updates

Quasar may periodically check for available updates. This request includes only your current launcher version number and operating system platform. No personal information is included.

7. Children's Privacy

Quasar is not directed at children. Users must comply with Microsoft's and Mojang's age requirements to hold a Minecraft account. We do not knowingly collect personal information from any user, including minors, as all data is stored locally on the user's device.

8. Data Retention and Deletion

Because all data is stored locally on your device, you have full control over it at all times. You can remove your accounts, delete instance data, or uninstall Quasar entirely to erase all locally stored information. We have no server-side data to delete on your behalf.

9. Changes to This Policy

We may update this Privacy Policy from time to time. The effective date at the top of this page will reflect the latest revision. Continued use of Quasar after changes are posted constitutes your acceptance of the revised policy.

10. Contact

If you have questions or concerns about this Privacy Policy, please contact us at [email protected].