export declare const DefaultProgressComponent: import("@backstage/frontend-plugin-api").ExtensionDefinition<{
    config: {};
    configInput: {};
    output: import("@backstage/frontend-plugin-api").ConfigurableExtensionDataRef<{
        ref: import("@backstage/frontend-plugin-api").ComponentRef;
        impl: import("react").ComponentType;
    }, "core.component.component", {}>;
    inputs: {
        [x: string]: import("@backstage/frontend-plugin-api").ExtensionInput<import("@backstage/frontend-plugin-api").AnyExtensionDataRef, {
            optional: boolean;
            singleton: boolean;
        }>;
    };
    params: never;
    kind: "component";
    name: string;
}>;
export declare const DefaultNotFoundErrorPageComponent: import("@backstage/frontend-plugin-api").ExtensionDefinition<{
    config: {};
    configInput: {};
    output: import("@backstage/frontend-plugin-api").ConfigurableExtensionDataRef<{
        ref: import("@backstage/frontend-plugin-api").ComponentRef;
        impl: import("react").ComponentType;
    }, "core.component.component", {}>;
    inputs: {
        [x: string]: import("@backstage/frontend-plugin-api").ExtensionInput<import("@backstage/frontend-plugin-api").AnyExtensionDataRef, {
            optional: boolean;
            singleton: boolean;
        }>;
    };
    params: never;
    kind: "component";
    name: string;
}>;
export declare const DefaultErrorBoundaryComponent: import("@backstage/frontend-plugin-api").ExtensionDefinition<{
    config: {};
    configInput: {};
    output: import("@backstage/frontend-plugin-api").ConfigurableExtensionDataRef<{
        ref: import("@backstage/frontend-plugin-api").ComponentRef;
        impl: import("react").ComponentType;
    }, "core.component.component", {}>;
    inputs: {
        [x: string]: import("@backstage/frontend-plugin-api").ExtensionInput<import("@backstage/frontend-plugin-api").AnyExtensionDataRef, {
            optional: boolean;
            singleton: boolean;
        }>;
    };
    params: never;
    kind: "component";
    name: string;
}>;