https://twitter.com/ravindUwU/status/1797479720130691350

changePwaManifest.js

/**
 * Finds the <link>ed PWA manifest (https://developer.mozilla.org/docs/Web/Manifest) and changes its
 * properties. Then, updates the <link> to a data URL with the contents of the changed manifest.
 *
 * It's possible that this might prevent manifest updates (https://web.dev/articles/manifest-updates)
 * but I'm unsure; haven't investigated this.
 */
(async () => {
	// Get manifest JSON.
	const link = document.querySelector('link[rel="manifest"]');
	const manifest = await (await fetch(link.href)).json();

	// Change properties of the manifest here.
	manifest.start_url = '/owo';
	delete manifest.scope;

	// Update <link>.
	link.href = `data:application/manifest+json;base64,${btoa(JSON.stringify(manifest))}`;
})();