diff --git a/server/src/modes/script/javascript.ts b/server/src/modes/script/javascript.ts
index 9f46023a20..0cf1f3be19 100644
--- a/server/src/modes/script/javascript.ts
+++ b/server/src/modes/script/javascript.ts
@@ -833,7 +833,7 @@ export async function getJavascriptMode(
       const { spans } = service.getEncodedSemanticClassifications(
         fileFsPath,
         textSpan,
-        tsModule.SemanticClassificationFormat.TwentyTwenty
+        tsModule.SemanticClassificationFormat?.TwentyTwenty
       );
 
       const data: SemanticTokenOffsetData[] = [];