CSS next-sibling combinator doesn't work if template is inside snippet

[mary-ext]

Describe the bug

using CSS next-sibling combinator .a + .b doesn't work as Svelte considers it unused when the template is inside a snippet.

Reproduction

Playground link

{@render Thing("foo")}
{@render Thing("bar")}

{#snippet Thing(label)}
	<div class="thing">{label}</div>
{/snippet}

<style>
	.thing {
		& + & {
			color: red;
		}
	}

	.thing + .thing {
		color: red;
	}
</style>

The second <div.thing> is expected to have a red text color.

Logs

Not applicable.

System Info

Not applicable, playground link provided.

Severity

annoyance