diff --git a/src/vs/languages/html/common/htmlTags.ts b/src/vs/languages/html/common/htmlTags.ts
index db83d17ce6b2a3050362a026cc252d3b9b20080a..f09b700692a6b4a1598304a3c6faf31837367a8e 100644
--- a/src/vs/languages/html/common/htmlTags.ts
+++ b/src/vs/languages/html/common/htmlTags.ts
@@ -76,8 +76,10 @@ export function getHTML5TagProvider(): IHTMLTagProvider {
 		u: none,
 		mark: none,
 		ruby: none,
-		rt: none,
+		rb: none,
 		rp: none,
+		rt: none,
+		rtc: none,
 		bdi: none,
 		bdo: none,
 		span: none,