4 files changed, 5 insertions, 5 deletions
diff --git a/packages/integrations/lit/client-shim.js b/packages/integrations/lit/client-shim.js
index ca97b92cc..c457710b7 100644
--- a/packages/integrations/lit/client-shim.js
+++ b/packages/integrations/lit/client-shim.js
@@ -8,7 +8,7 @@ async function polyfill() {
 }
 
 const polyfillCheckEl = new DOMParser()
-	.parseFromString(`<p><template shadowroot="open"></template></p>`, 'text/html', {
+	.parseFromString(`<p><template shadowroot="open" shadowrootmode="open"></template></p>`, 'text/html', {
 		includeShadowRoots: true,
 	})
 	.querySelector('p');
diff --git a/packages/integrations/lit/client-shim.min.js b/packages/integrations/lit/client-shim.min.js
index afae053ac..0965e6a78 100644
--- a/packages/integrations/lit/client-shim.min.js
+++ b/packages/integrations/lit/client-shim.min.js
@@ -8,7 +8,7 @@ var b = (t, n) => {
 function s() {
 	if (d === void 0) {
 		let t = document.createElement('div');
-		(t.innerHTML = '<div><template shadowroot="open"></template></div>'),
+		(t.innerHTML = '<div><template shadowroot="open" shadowrootmode="open"></template></div>'),
 			(d = !!t.firstElementChild.shadowRoot);
 	}
 	return d;
@@ -80,7 +80,7 @@ async function g() {
 	window.addEventListener('DOMContentLoaded', () => t(document.body), { once: true });
 }
 var x = new DOMParser()
-	.parseFromString('<p><template shadowroot="open"></template></p>', 'text/html', {
+	.parseFromString('<p><template shadowroot="open" shadowrootmode="open"></template></p>', 'text/html', {
 		includeShadowRoots: !0,
 	})
 	.querySelector('p');
diff --git a/packages/integrations/lit/server.js b/packages/integrations/lit/server.js
index 48a3c646f..da571466f 100644
--- a/packages/integrations/lit/server.js
+++ b/packages/integrations/lit/server.js
@@ -62,7 +62,7 @@ function* render(Component, attrs, slots) {
 	yield `>`;
 	const shadowContents = instance.renderShadow({});
 	if (shadowContents !== undefined) {
-		yield '<template shadowroot="open">';
+		yield '<template shadowroot="open" shadowrootmode="open">';
 		yield* shadowContents;
 		yield '</template>';
 	}
diff --git a/packages/integrations/lit/test/server.test.js b/packages/integrations/lit/test/server.test.js
index e7b5e98f9..439c0877d 100644
--- a/packages/integrations/lit/test/server.test.js
+++ b/packages/integrations/lit/test/server.test.js
@@ -38,7 +38,7 @@ describe('renderToStaticMarkup', () => {
 		customElements.define(tagName, class extends LitElement {});
 		const render = await renderToStaticMarkup(tagName);
 		expect(render).to.deep.equal({
-			html: `<${tagName}><template shadowroot="open"><!--lit-part--><!--/lit-part--></template></${tagName}>`,
+			html: `<${tagName}><template shadowroot="open" shadowrootmode="open"><!--lit-part--><!--/lit-part--></template></${tagName}>`,
 		});
 	});