Function send

packages/react-devtools-extensions/src/contentScripts/backendManager.js:136–145

(event: string, payload: any, transferable?: Array<any>)

      };
    },
    send(event: string, payload: any, transferable?: Array<any>) {
      window.postMessage(
        {
          source: 'react-devtools-bridge',
          payload: {event, payload},
        },
        '*',
        transferable,
      );
    },
  });

  const agent = new Agent(