Inside a load function (as well as in form actions, hooks and API routes, which we’ll learn about later) you have access to a setHeaders function, which — unsurprisingly — can be used to set headers on the response.

Most commonly, you’d use it to customise caching behaviour with the Cache-Control response header, but for the sake of this tutorial we’ll do something less advisable and more dramatic:

export function load({ setHeaders }) {
	setHeaders({
		'Content-Type': 'text/plain'
	});
}

(You may need to reload the iframe to see the effect.)