Hide empty subnavigations and their buttons in mobile view

public/typo3conf/ext/ep_theme/Resources/Private/Partials/Mobilenav.html

@@ -124,6 +124,7 @@
                            title="{subitem.title}">
                             {subitem.title}
                         </a>
+                        <f:if condition="{subitem.children}">
                             <button type="button"
                                     class="focus:outline-none"
                                     data-action="collapse#toggle">
@@ -131,7 +132,9 @@
                                     <use href="#icon-chevron-down"></use>
                                 </svg>
                             </button>
+                        </f:if>
                     </div>
+                    <f:if condition="{subitem.children}">
                         <div class="transform pt-2"
                              data-collapse-target="container">
                             <f:for each="{subitem.children}" as="subsubitem">
@@ -145,6 +148,7 @@
                                 </a>
                             </f:for>
                         </div>
+                    </f:if>
                 </li>
             </f:for>
         </ul>