diff --git a/src/generators/dom/visitors/Element/Element.ts b/src/generators/dom/visitors/Element/Element.ts
index 114482f649..49eeab2bef 100644
--- a/src/generators/dom/visitors/Element/Element.ts
+++ b/src/generators/dom/visitors/Element/Element.ts
@@ -102,7 +102,7 @@ export default function visitElement(
 
 		if (node._cssRefAttribute) {
 			block.builders.hydrate.addLine(
-				`@setAttribute(${name}, "svelte-ref-${node._cssRefAttribute}", ");`
+				`@setAttribute(${name}, "svelte-ref-${node._cssRefAttribute}", "");`
 			)
 		}
 	}
diff --git a/test/css/index.js b/test/css/index.js
index 5832c4070c..65867b294a 100644
--- a/test/css/index.js
+++ b/test/css/index.js
@@ -1,6 +1,7 @@
 import assert from 'assert';
 import * as fs from 'fs';
-import { env, normalizeHtml, svelte } from '../helpers.js';
+import { parse } from 'acorn';
+import { addLineNumbers, env, normalizeHtml, svelte } from '../helpers.js';
 
 function tryRequire(file) {
 	try {
@@ -22,6 +23,15 @@ function normalizeWarning(warning) {
 	return warning;
 }
 
+function checkCodeIsValid(code) {
+	try {
+		parse(code);
+	} catch (err) {
+		console.error(addLineNumbers(code));
+		throw new Error(err.message);
+	}
+}
+
 describe('css', () => {
 	fs.readdirSync('test/css/samples').forEach(dir => {
 		if (dir[0] === '.') return;
@@ -67,6 +77,10 @@ describe('css', () => {
 				})
 			);
 
+			// check the code is valid
+			checkCodeIsValid(dom.code);
+			checkCodeIsValid(ssr.code);
+
 			assert.equal(dom.css, ssr.css);
 
 			assert.deepEqual(
diff --git a/test/validator/index.js b/test/validator/index.js
index 1c718fae80..176d060faf 100644
--- a/test/validator/index.js
+++ b/test/validator/index.js
@@ -2,7 +2,7 @@ import * as fs from "fs";
 import assert from "assert";
 import { svelte, tryToLoadJson } from "../helpers.js";
 
-describe.only("validate", () => {
+describe("validate", () => {
 	fs.readdirSync("test/validator/samples").forEach(dir => {
 		if (dir[0] === ".") return;