= () => { const url = new URL('AD_SERVER_ENDPOINT') url.searchParams = { /*...*/ } return fetch(
 url.toString(),
 { headers: { /*...*/ } }
 ).then((res) => res.json()) } Comlink.expose(request) // main.js const request = Comlink.wrap(
 new Worker(paths.controllerWorker) ) // ...
 if (useWorker) { request(sectionId).then(renderAd) } Off The Main Thread ࠂεΫϦϓτͷ࠷దԽ