: The easiest way to browse and install large modpack libraries. Are you trying to configure a specific UI theme or Minecraft Launcher

For developers using the Fabric Loader , "Main Only" often describes initialization entrypoints:

: It determines if a specific UI element (skin) should only be active in the Main Hub and automatically disable itself when you switch to a Sub Hub .

: Certain mod initializers (like client or server ) are designed to run only after the main entrypoint has executed.

: The standard tool for playing the vanilla Java and Bedrock Editions .

: The main entrypoint is the first normal initialization to run for any Fabric-based mod. 3. General Minecraft Launchers

: It is generally recommended to keep this option disabled unless you are specifically setting up a "Mix & Match" layout to switch between different interface themes. 2. Minecraft Modding (Fabric Loader)