diff --git a/src/vs/base/browser/ui/menu/menu.ts b/src/vs/base/browser/ui/menu/menu.ts
index e9bfa3fb980f6966ae4401c7b9bde57433985885..1cf6cf7075361267e10803e4c08a9e6a58a54eaf 100644
--- a/src/vs/base/browser/ui/menu/menu.ts
+++ b/src/vs/base/browser/ui/menu/menu.ts
@@ -59,7 +59,7 @@ export class Menu extends ActionBar {
 	private menuDisposables: IDisposable[];
 	private scrollableElement: DomScrollableElement;
 	private menuElement: HTMLElement;
-	private scrollTopHold: number;
+	private scrollTopHold: number | undefined;
 
 	private readonly _onScroll: Emitter<void>;