don't hash @html because it's not guranteed that input is the same on the server and client

src/compiler/compile/nodes/RawMustacheTag.ts

@@ -4,6 +4,7 @@ export default class RawMustacheTag extends Tag {
 	type: 'RawMustacheTag';
 	constructor(component, parent, scope, info) {
 		super(component, parent, scope, info);
+		this.cannot_use_innerhtml();
 		this.not_static_content();
 	}
 }

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

@@ -36,7 +36,7 @@ export default class RawMustacheTagWrapper extends Tag {
 				content => insert(content)
 			);
 
-			block.chunks.mount.push(b`if (@get_svelte_dataset(${parent_node}) !== "${hash(JSON.stringify(this.node.expression.node))}") ${insert(init)}`);
+			block.chunks.mount.push(insert(init));
 		} else {
 			const needs_anchor = in_head || (this.next ? !this.next.is_dom_node() : (!this.parent || !this.parent.is_dom_node()));
 

src/compiler/compile/render_ssr/Renderer.ts

@@ -49,7 +49,6 @@ export interface RenderOptions extends CompileOptions{
 	locate: (c: number) => { line: number; column: number };
 	head_id?: string;
 	has_added_svelte_hash?: boolean;
-	optimised_html_hydration?: boolean;
 }
 
 export default class Renderer {

src/compiler/compile/render_ssr/handlers/Element.ts

@@ -160,10 +160,7 @@ export default function (node: Element, renderer: Renderer, options: RenderOptio
 	});
 
 	if (options.hydratable) {
-		if (node.children.length === 1 && node.children[0].type === 'RawMustacheTag') {
+		if (node.can_optimise_to_html_string && !options.has_added_svelte_hash) {
-			renderer.add_string(` data-svelte-h="${hash(JSON.stringify(node.children[0].expression.node))}"`);
-			options = { ...options, optimised_html_hydration: true };
-		} else if (node.can_optimise_to_html_string && !options.has_added_svelte_hash) {
 			renderer.add_string(` data-svelte-h="${node.hash()}"`);
 			options = { ...options, has_added_svelte_hash: true };
 		}

src/compiler/compile/render_ssr/handlers/HtmlTag.ts

@@ -3,7 +3,7 @@ import RawMustacheTag from '../../nodes/RawMustacheTag';
 import { Expression } from 'estree';
 
 export default function(node: RawMustacheTag, renderer: Renderer, options: RenderOptions) {
-	if (options.hydratable && !options.optimised_html_hydration) renderer.add_string('<!-- HTML_TAG_START -->');
+	if (options.hydratable) renderer.add_string('<!-- HTML_TAG_START -->');
 	renderer.add_expression(node.expression.node as Expression);
-	if (options.hydratable && !options.optimised_html_hydration) renderer.add_string('<!-- HTML_TAG_END -->');
+	if (options.hydratable) renderer.add_string('<!-- HTML_TAG_END -->');
 }