Restrict max-height of manager menu

src/components/Menu/ManagerMenu.js

@@ -2,6 +2,7 @@ import { uniq } from 'lodash-es';
 import React from 'react';
 import { Button, Glyphicon, MenuItem, NavDropdown } from 'react-bootstrap';
 import { LinkContainer } from 'react-router-bootstrap';
+import styles from './Menu.module.css';
 
 class ManagerMenu extends React.Component {
   getBeamlineList(instruments) {
@@ -97,6 +98,7 @@ class ManagerMenu extends React.Component {
         eventKey={3}
         title={navDropdownTitle}
         id="basic-nav-dropdown"
+        className={styles.managerMenu}
       >
         <LinkContainer to="/usermanagement">
           <MenuItem eventKey={3.3}>

src/components/Menu/Menu.module.css

@@ -6,3 +6,9 @@
   display: flex;
   align-items: center;
 }
+
+.managerMenu > :global(.dropdown-menu) {
+  max-height: 40rem;
+  overflow: hidden scroll;
+  scrollbar-width: thin;
+}