feature: add displayStartEndDates poll option

src/styles/left-nav/_index.scss

@@ -220,15 +220,15 @@ nav#main__menu {
 
   /* The little cross icon on contacts' name appears or disapear + hover + styles */
   .sub-menu__contacts>div>solid-display {
+    height: 28px;
+    display: block;
 
     hubl-menu-contact-removed {
       display: none;
+      button {
+        visibility: hidden;
+      }
     }
-  }
-
-  .sub-menu__contacts>div>solid-display {
-    height: 28px;
-    display: block;
 
     &:hover {
 
@@ -257,7 +257,8 @@ nav#main__menu {
         padding-top: 5px;
 
         button {
-        
+          visibility: visible;
+
           &::before {
             font-size: 18px;
             color: white;