Interface RPCPortInternal

interface RPCPort {
    addEventListener(type: "message", listener: (ev: any) => void): void;
    off(event: "message", listener: (value: unknown) => void): this;
    on(event: "message" | "online", listener: (value: unknown) => void): this;
    postMessage(value: unknown, transfer?: TransferListItem[]): void;
    removeEventListener(type: "message", listener: (ev: any) => void): void;
}