refactor: use event listener to listen for page load event

src/main/resources/templates/index.html

@@ -51,7 +51,7 @@
     </main>
     <script th:src="@{/scripts.js}"></script>
     <script>
-        window.onload = () => {
+        window.addEventListener('load', () => {
             let keyBindings = {
                 'w': 'first-page-link',
                 'a': 'prev-page-link',
@@ -66,7 +66,7 @@
                     }
                 }
             };
-        };
+        });
     </script>
 </body>
 </html>