html anchor in head

[tanhauhau]

While studying for #5012, i found that {@html} in <svelte:head> should always have an anchor, even before v3.7

svelte/src/compiler/compile/render_dom/wrappers/RawMustacheTag.ts

Lines 28 to 44 in 324be53

	// if in head always needs anchors
	if (in_head) {
	this.prev = null;
	this.next = null;
	}
	// TODO use is_dom_node instead of type === 'Element'?
	const needs_anchor_before = this.prev ? this.prev.node.type !== 'Element' : needs_anchors;
	const needs_anchor_after = this.next ? this.next.node.type !== 'Element' : needs_anchors;
	const anchor_before = needs_anchor_before
	? block.get_unique_name(`${name}_before`)
	: (this.prev && this.prev.var) || 'null';
	const anchor_after = needs_anchor_after
	? block.get_unique_name(`${name}_after`)
	: (this.next && this.next.var) || 'null';

without anchor, updating the raw {@html} tag may shift the html elements, and may cause css specificity inconsistency.

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Tests

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[Conduitry]

This fix is included in 3.24.0.