Backstage
    Preparing search index...
    ThemeBlueprint: ExtensionBlueprint<
        {
            config: {};
            configInput: {};
            dataRefs: {
                theme: ConfigurableExtensionDataRef<AppTheme, "core.theme.theme", {}>;
            };
            inputs: {};
            kind: "theme";
            output: ExtensionDataRef<AppTheme, "core.theme.theme", {}>;
            params: { theme: AppTheme };
        },
    > = ...

    Creates an extension that adds/replaces an app theme.