Function spawnCrossOriginWorker

runtime/src/index.js:148–156

(workerUrl)

/* Blob URL inherits the page's origin -> sidesteps Chromium's cross-origin block; the imported module then loads under CORS (Cloudflare Pages OK by default). `Function.toString` keeps the bootstrap as real JS in source. */
function spawnCrossOriginWorker(workerUrl) {
    const source = `(${crossOriginBootstrap.toString()})(${JSON.stringify(workerUrl)});`;
    const blob = new Blob([source], { type: 'application/javascript' });
    const blobUrl = URL.createObjectURL(blob);
    const worker = new Worker(blobUrl, { type: 'module' });
    // Defer revoke a tick; some browsers race it against the module fetch.
    setTimeout(() => URL.revokeObjectURL(blobUrl), 0);
    return worker;
}