Tögl, Christina
--- a/packages/app-shell/src/app-shell.js
+++ b/packages/app-shell/src/app-shell.js

+        if (this.menuHeight === -1) {
+            this.menuHeight = menu.clientHeight;
+        }
+
+        let topValue = subtitle.getBoundingClientRect().bottom;
+        let isMenuOverflow = this.menuHeight + topValue >= window.innerHeight ? true : false;
+        
+        if (isMenuOverflow && !menu.classList.contains('hidden')) {
+            menu.setAttribute('style', 'position: fixed;top: ' + topValue + 'px;bottom: 0;border-bottom: 0;overflow-y: auto;');
+            menu.scrollTop = 0;
+            document.body.setAttribute('style', 'overflow:hidden;');
+        
+        } else if (isMenuOverflow && menu.classList.contains('hidden')) {
+            document.body.removeAttribute('style', 'overflow:hidden;');
+            menu.removeAttribute('style', 'position: fixed;top: ' + topValue + 'px;bottom: 0;border-bottom: 0;overflow-y: auto;');