diff --git a/extensions/typescript-language-features/src/features/bufferSyncSupport.ts b/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
index d18304c63eebd05796216887fe8923641c579f65..d180d95c460205296f86b815ac33a3dedbbe65fb 100644
--- a/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
+++ b/extensions/typescript-language-features/src/features/bufferSyncSupport.ts
@@ -274,17 +274,15 @@ export default class BufferSyncSupport extends Disposable {
 	}
 
 	public interuptGetErr<R>(f: () => R): R {
-		// TODO: re-enable for 1.27 insiders
-		return f();
-		// if (!this.pendingGetErr) {
-		// 	return f();
-		// }
-
-		// this.pendingGetErr.cancel();
-		// this.pendingGetErr = undefined;
-		// const result = f();
-		// this.triggerDiagnostics();
-		// return result;
+		if (!this.pendingGetErr) {
+			return f();
+		}
+
+		this.pendingGetErr.cancel();
+		this.pendingGetErr = undefined;
+		const result = f();
+		this.triggerDiagnostics();
+		return result;
 	}
 
 	private onDidCloseTextDocument(document: vscode.TextDocument): void {