diff --git a/UI/Templates/MailerUI/UIxMailEditor.wox b/UI/Templates/MailerUI/UIxMailEditor.wox
index 309444a88..52b96631e 100644
--- a/UI/Templates/MailerUI/UIxMailEditor.wox
+++ b/UI/Templates/MailerUI/UIxMailEditor.wox
@@ -82,15 +82,23 @@
                     label:placeholder="Add a recipient">
                   <md-item-template>
                     <div class="sg-tile-content">
-                      <div class="sg-md-subhead"
-                            md-highlight-text="editor.autocomplete.to.searchText"
-                            md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.to.searchText) }}</div>
+                      <div class="sg-md-subhead">
+                        <div md-highlight-text="editor.autocomplete.to.searchText"
+                             md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.to.searchText) }}</div>
+                      </div>
                       <div class="sg-md-body"
                            md-colors="::{color: 'default-background-500'}">{{ user.containername }}</div>
                     </div>
                   </md-item-template>
                 </md-autocomplete>
-                <md-chip-template>{{$chip}}</md-chip-template>
+                <md-chip-template>
+                  <div class="sg-tile-content">
+                    {{$chip}}
+                    <md-button class="sg-tile-btn" md-colors="::{ color: 'accent-600'}" ng-if="$chip.isExpandable" ng-click="editor.expandGroup($chip, 'to')">
+                      <md-icon md-colors="::{ color: 'accent-600'}">add_box</md-icon><span ng-bind="$chip.members.length"></span>
+                    </md-button>
+                  </div>
+                </md-chip-template>
               </md-chips>
             </div>
 
@@ -115,15 +123,23 @@
                     label:placeholder="Add a recipient">
                   <md-item-template>
                     <div class="sg-tile-content">
-                      <div class="sg-md-subhead"
-                            md-highlight-text="editor.autocomplete.cc.searchText"
-                            md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.cc.searchText) }}</div>
+                      <div class="sg-md-subhead">
+                        <div md-highlight-text="editor.autocomplete.cc.searchText"
+                             md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.cc.searchText) }}</div>
+                      </div>
                       <div class="sg-md-body"
                            md-colors="::{color: 'default-background-500'}">{{ user.containername }}</div>
                     </div>
                   </md-item-template>
                 </md-autocomplete>
-                <md-chip-template>{{$chip}}</md-chip-template>
+                <md-chip-template>
+                  <div class="sg-tile-content">
+                    {{$chip}}
+                    <md-button class="sg-tile-btn" md-colors="::{ color: 'accent-600'}" ng-if="$chip.isExpandable" ng-click="editor.expandGroup($chip, 'cc')">
+                      <md-icon md-colors="::{ color: 'accent-600'}">add_box</md-icon><span ng-bind="$chip.members.length"></span>
+                    </md-button>
+                  </div>
+                </md-chip-template>
               </md-chips>
             </div>
 
@@ -148,15 +164,23 @@
                     label:placeholder="Add a recipient">
                   <md-item-template>
                     <div class="sg-tile-content">
-                      <div class="sg-md-subhead"
-                            md-highlight-text="editor.autocomplete.bcc.searchText"
-                            md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.bcc.searchText) }}</div>
+                      <div class="sg-md-subhead">
+                        <div md-highlight-text="editor.autocomplete.bcc.searchText"
+                             md-highlight-flags="gi">{{ user.$shortFormat(editor.autocomplete.bcc.searchText) }}</div>
+                      </div>
                       <div class="sg-md-body"
                            md-colors="::{color: 'default-background-500'}">{{ user.containername }}</div>
                     </div>
                   </md-item-template>
                 </md-autocomplete>
-                <md-chip-template>{{$chip}}</md-chip-template>
+                <md-chip-template>
+                  <div class="sg-tile-content">
+                    {{$chip}}
+                    <md-button class="sg-tile-btn" md-colors="::{ color: 'accent-600'}" ng-if="$chip.isExpandable" ng-click="editor.expandGroup($chip, 'bcc')">
+                      <md-icon md-colors="::{ color: 'accent-600'}">add_box</md-icon><span ng-bind="$chip.members.length"></span>
+                    </md-button>
+                  </div>
+                </md-chip-template>
               </md-chips>
             </div>
 
diff --git a/UI/Templates/SchedulerUI/UIxAttendeesEditor.wox b/UI/Templates/SchedulerUI/UIxAttendeesEditor.wox
index 35346684f..0d1c7c2ec 100644
--- a/UI/Templates/SchedulerUI/UIxAttendeesEditor.wox
+++ b/UI/Templates/SchedulerUI/UIxAttendeesEditor.wox
@@ -70,8 +70,8 @@
           <div class="sg-md-subhead"><div>{{currentAttendee.name}}</div></div>
           <div class="sg-md-body">
             <div>{{currentAttendee.email}}</div>
-            <md-button class="sg-tile-thread" md-colors="::{ color: 'accent-600'}" ng-if="currentAttendee.isExpandableGroup" ng-click="editor.expandAttendee(currentAttendee)">
-              <md-icon class="md-rotate-180-ccw" md-colors="::{ color: 'accent-600'}">add_box</md-icon><span ng-bind="currentAttendee.members.length"></span>
+            <md-button class="sg-tile-btn" md-colors="::{ color: 'accent-600'}" ng-if="currentAttendee.isExpandableGroup" ng-click="editor.expandAttendee(currentAttendee)">
+              <md-icon md-colors="::{ color: 'accent-600'}">add_box</md-icon><span ng-bind="currentAttendee.members.length"></span>
             </md-button>
           </div>
         </div>
diff --git a/UI/WebServerResources/js/Contacts/Card.service.js b/UI/WebServerResources/js/Contacts/Card.service.js
index 50d256f0c..e2badad8e 100644
--- a/UI/WebServerResources/js/Contacts/Card.service.js
+++ b/UI/WebServerResources/js/Contacts/Card.service.js
@@ -254,7 +254,7 @@
     if (this.members)
       return Card.$q.when(this.members);
 
-    if (this.isgroup) {
+    if (this.$isGroup({expandable: true})) {
       return Card.$$resource.fetch(this.$path(), 'members').then(function(data) {
         _this.members = _.map(data.members, function(member) {
           return new Card(member);
@@ -262,6 +262,8 @@
         return _this.members;
       });
     }
+
+    return Card.$q.reject("Card " + this.id + " is not an LDAP group");
   };
 
   /**
@@ -429,6 +431,11 @@
     return this.c_component == 'vlist' && condition;
   };
 
+  Card.prototype.$isGroup = function(options) {
+    var condition = (!options || !options.expandable || options.expandable && Card.$Preferences.defaults.SOGoLDAPGroupExpansionEnabled);
+    return this.isgroup && condition;
+  };
+
   Card.prototype.$addOrg = function(org) {
     if (angular.isUndefined(this.orgs)) {
       this.orgs = [org];
diff --git a/UI/WebServerResources/js/Mailer/Message.service.js b/UI/WebServerResources/js/Mailer/Message.service.js
index 1b1316b02..687b880ab 100644
--- a/UI/WebServerResources/js/Mailer/Message.service.js
+++ b/UI/WebServerResources/js/Mailer/Message.service.js
@@ -745,7 +745,7 @@
    */
   Message.prototype.$save = function() {
     var _this = this,
-        data = this.editable;
+        data = this.$omit();
 
     Message.$log.debug('save = ' + JSON.stringify(data, undefined, 2));
 
@@ -765,7 +765,7 @@
    */
   Message.prototype.$send = function() {
     var _this = this,
-        data = angular.copy(this.editable);
+        data = this.$omit();
 
     Message.$log.debug('send = ' + JSON.stringify(data, undefined, 2));
 
@@ -828,8 +828,13 @@
   Message.prototype.$omit = function(options) {
     var message = {},
         privateAttributes = options && options.privateAttributes;
-    angular.forEach(this, function(value, key) {
-      if (key != 'constructor' && key[0] != '$' || privateAttributes) {
+    angular.forEach(this.editable, function(value, key) {
+      if (_.includes(['to', 'cc', 'bcc'], key)) {
+        message[key] = _.map(value, function (addr) {
+          return addr.toString();
+        });
+      }
+      else if (key != 'constructor' && key[0] != '$' || privateAttributes) {
         message[key] = value;
       }
     });
diff --git a/UI/WebServerResources/js/Mailer/MessageEditorController.js b/UI/WebServerResources/js/Mailer/MessageEditorController.js
index c4bff36e7..9764cc438 100644
--- a/UI/WebServerResources/js/Mailer/MessageEditorController.js
+++ b/UI/WebServerResources/js/Mailer/MessageEditorController.js
@@ -329,6 +329,16 @@
           });
         }
       }
+      else if (contact.$isGroup({expandable: true})) {
+        recipient = {
+          toString: function () { return contact.$shortFormat(); },
+          isExpandable: true,
+          members: []
+        };
+        contact.$members().then(function (members) {
+          recipient.members = members;
+        });
+      }
       else {
         recipient = contact.$shortFormat();
       }
@@ -339,6 +349,16 @@
         return null;
     }
 
+    this.expandGroup = function(contact, field) {
+      var recipients, i, j;
+      recipients = vm.message.editable[field];
+      i = recipients.indexOf(contact);
+      recipients.splice(i, 1);
+      for (j = 0; j < contact.members.length; j++) {
+        recipients.splice(i + j, 0, contact.members[j].$shortFormat());
+      }
+    };
+
     // Drafts autosaving
     function autosaveDrafts() {
       vm.message.$save();
diff --git a/UI/WebServerResources/js/Mailer/sgMessageListItemMain.directive.js b/UI/WebServerResources/js/Mailer/sgMessageListItemMain.directive.js
index 8fa2b1ac4..bff593031 100644
--- a/UI/WebServerResources/js/Mailer/sgMessageListItemMain.directive.js
+++ b/UI/WebServerResources/js/Mailer/sgMessageListItemMain.directive.js
@@ -26,7 +26,7 @@
         '  <div class="sg-md-body">',
         '    <div class="sg-tile-subject"><!-- subject --></div>',
         '    <div class="sg-tile-size"><!-- size --></div>',
-        '    <md-button class="sg-tile-thread md-secondary ng-hide" md-colors="::{ color: \'accent-600\'}" ng-click="$ctrl.toggleThread()">',
+        '    <md-button class="sg-tile-btn md-secondary ng-hide" md-colors="::{ color: \'accent-600\'}" ng-click="$ctrl.toggleThread()">',
         '      <md-icon class="md-rotate-180-ccw" md-colors="::{ color: \'accent-600\'}">expand_more</md-icon><span></span>', // expanded by default (icon is rotated)
         '    </md-button>',
         '  </div>',
diff --git a/UI/WebServerResources/scss/components/chips/chips.scss b/UI/WebServerResources/scss/components/chips/chips.scss
index 66cd5f586..800ebf801 100644
--- a/UI/WebServerResources/scss/components/chips/chips.scss
+++ b/UI/WebServerResources/scss/components/chips/chips.scss
@@ -72,6 +72,9 @@ md-chips {
       width: 100%;
     }
   }
+  .sg-tile-btn {
+    margin-right: 3px !important; // assume the button is right before the close button
+  }
 }
 
 // Adapting avatars in contact chips to the new material guidelines
diff --git a/UI/WebServerResources/scss/components/list/list.scss b/UI/WebServerResources/scss/components/list/list.scss
index 383e1c7ba..90894a3ba 100644
--- a/UI/WebServerResources/scss/components/list/list.scss
+++ b/UI/WebServerResources/scss/components/list/list.scss
@@ -176,7 +176,7 @@ div.md-tile-left {
   &-tile-content {
     flex: 1;
     overflow: hidden; // required in Firefox
-    .sg-tile-date, .sg-tile-size, .sg-tile-thread {
+    .sg-tile-date, .sg-tile-size, .sg-tile-btn {
       flex-shrink: 0;
       font-size: sg-size(body);
       font-weight: $sg-font-light;
@@ -186,7 +186,7 @@ div.md-tile-left {
     .sg-tile-size {
       font-size: sg-size(caption);
     }
-    .sg-tile-thread {
+    .sg-tile-btn {
       min-height: auto;
       min-width: auto;
       padding: 0 3px !important;