diff --git a/core/src/utils/browser/index.ts b/core/src/utils/browser/index.ts
index 5b3e914a45..ed70843de1 100644
--- a/core/src/utils/browser/index.ts
+++ b/core/src/utils/browser/index.ts
@@ -20,6 +20,26 @@
  * Note: Code inside of this if-block will
  * not run in an SSR environment.
  */
-export const win: Window | undefined = typeof window !== 'undefined' ? window : undefined;
+
+/**
+ * Even listeners on the window typically expect
+ * Event types for the listener parameter. If you want to listen
+ * on the window for certain CustomEvent types you can add that definition
+ * here as long as you are using the "win" utility below.
+ */
+type IonicWindow = Window & {
+  addEventListener(
+    type: 'ionKeyboardDidShow',
+    listener: (ev: CustomEvent<{ keyboardHeight: number }>) => void,
+    options?: boolean | AddEventListenerOptions
+  ): void;
+  removeEventListener(
+    type: 'ionKeyboardDidShow',
+    listener: (ev: CustomEvent<{ keyboardHeight: number }>) => void,
+    options?: boolean | AddEventListenerOptions
+  ): void;
+};
+
+export const win: IonicWindow | undefined = typeof window !== 'undefined' ? window : undefined;
 
 export const doc: Document | undefined = typeof document !== 'undefined' ? document : undefined;
diff --git a/core/src/utils/input-shims/hacks/scroll-assist.ts b/core/src/utils/input-shims/hacks/scroll-assist.ts
index 93d84d8090..1b35367ce9 100644
--- a/core/src/utils/input-shims/hacks/scroll-assist.ts
+++ b/core/src/utils/input-shims/hacks/scroll-assist.ts
@@ -13,18 +13,6 @@ let currentPadding = 0;
 
 const SKIP_SCROLL_ASSIST = 'data-ionic-skip-scroll-assist';
 
-/**
- * addEventListener typically expects an Event
- * type in the event listener callbacks. In this case
- * we have a CustomEvent, so we update the window event map
- * to register our specific event as well as the type of that event.
- */
-declare global {
-  interface WindowEventMap {
-    ionKeyboardDidShow: CustomEvent<{ keyboardHeight: number }>;
-  }
-}
-
 export const enableScrollAssist = (
   componentEl: HTMLElement,
   inputEl: HTMLInputElement | HTMLTextAreaElement,
@@ -135,7 +123,7 @@ export const enableScrollAssist = (
    */
   const focusOut = () => {
     hasKeyboardBeenPresentedForTextField = false;
-    window.removeEventListener('ionKeyboardDidShow', keyboardShow);
+    win?.removeEventListener('ionKeyboardDidShow', keyboardShow);
     componentEl.removeEventListener('focusout', focusOut, true);
   };
 
@@ -166,7 +154,7 @@ export const enableScrollAssist = (
       platformHeight
     );
 
-    window.addEventListener('ionKeyboardDidShow', keyboardShow);
+    win?.addEventListener('ionKeyboardDidShow', keyboardShow);
     componentEl.addEventListener('focusout', focusOut, true);
   };
 
@@ -174,7 +162,7 @@ export const enableScrollAssist = (
 
   return () => {
     componentEl.removeEventListener('focusin', focusIn, true);
-    window.removeEventListener('ionKeyboardDidShow', keyboardShow);
+    win?.removeEventListener('ionKeyboardDidShow', keyboardShow);
     componentEl.removeEventListener('focusout', focusOut, true);
   };
 };