DOCUMENTATION / MAKE IT YOURS
Launcher & runtime settings
The alpha retains inherited management pages, but official-launcher preparation has a narrower, explicit settings contract.
Library and appearance
Use Library for installed instances, Discover for catalog search and Import for supported existing packs. Dark and light appearance are available. Appearance and Launcher settings affect this app, not the official launcher's theme.
Language
Use the language page to choose an available application translation. A translated interface does not establish complete translation coverage or change a modpack's own language settings.
Minecraft and window settings
The official handoff maps configured width/height and resolved memory limits. Maximized-window settings, custom JVM arguments, hooks, custom components and native-library overrides are outside its supported mapping and can block preparation.
Per-instance settings
Check the selected instance before changing its settings. Memory and window preferences can differ from global defaults. After a supported change, Preview and Save the official installation again; the existing official profile is not silently rewritten.
Memory
Review minimum and maximum memory against the pack's requirements and system resources. Leave enough for Windows and other apps. More memory is not a general solution to loader or mod incompatibility.
Minecraft and loader versions
Use the pack's exact pins. Supported automatic preparation covers pinned Fabric/Quilt, modern Forge/NeoForge and recognized Minecraft 1.12.2 Forge LaunchWrapper formats. Other legacy/custom formats can be refused. Engine ancestry is not gameplay acceptance of every version.
Java settings and the Java wizard
In the closed-alpha handoff, the official Minecraft Launcher selects game Java. Inherited Java controls and its wizard do not change that boundary. Custom Java overrides block this preparation workflow; do not replace a runtime to work around a different loader error.
Services and catalog access
Catalog availability depends on the source and authorized build configuration. CurseForge currently uses website/import actions without authorized in-app API access. You do not need an Azure app registration or payment card for official-launcher sign-in. Never borrow another project's API credentials.
Network and proxy settings
Inherited proxy controls apply to this app's requests. They do not configure the official launcher's connection. For catalog failures, record the source and visible error; check ordinary connectivity before changing proxy settings. Keep proxy credentials out of support reports.
External tools
Inherited external-tool/profiler controls are not converted into the official-launcher handoff. Do not expect a configured tool or launch hook to run through that workflow. Ask for guidance before changing an accepted alpha setup to depend on one.
Preview, Save, Open, then Play
Close both apps before preparing an installation. Preview resolves the supported exact runtime and shows the intended settings. Save publishes the app-owned installation. Open starts the official client when available; choose the named UML installation, sign in and press Play there.
If an ownership/drift conflict is reported, preserve the installation and backups rather than deleting the receipt or blindly retrying. See the first-launch guide.