I find this bug just in testing in svelte.dev

Describe the bug
This code does not show "Hello Hello world!" after 1.5 seconds in expect:

<script>	let name = 'world';	setTimeout(() => {	name = 'Hello world!'	}, 1500) </script> <h1>Hello {name}!</h1> 

Maybe diff function is not work in expect?

I'm new to svelte, maybe this is just a feature ?