diff --git a/addons/mail/static/src/js/composer.js b/addons/mail/static/src/js/composer.js
index 184f1d66e82..e342074c5bd 100644
--- a/addons/mail/static/src/js/composer.js
+++ b/addons/mail/static/src/js/composer.js
@@ -145,24 +145,6 @@ var MentionManager = Widget.extend({
         return selections;
     },
 
-    proposition_navigation: function (keycode) {
-        var $active = this.$('.o_mention_proposition.active');
-        if (keycode === $.ui.keyCode.ENTER) { // selecting proposition
-            $active.click();
-        } else { // navigation in propositions
-            var $to;
-            if (keycode === $.ui.keyCode.DOWN) {
-                $to = $active.nextAll('.o_mention_proposition').first();
-            } else {
-                $to = $active.prevAll('.o_mention_proposition').first();
-            }
-            if ($to.length) {
-                $active.removeClass('active');
-                $to.addClass('active');
-            }
-        }
-    },
-
     /**
      * Detects if the user is currently typing a mention word
      * @return the search string if it is, false otherwise
@@ -286,6 +268,32 @@ var MentionManager = Widget.extend({
         }
         return result;
     },
+    /**
+     * @private
+     * @param {integer} keycode
+     */
+    _propositionNavigation: function (keycode) {
+        var $active = this.$('.o_mention_proposition.active');
+        if (keycode === $.ui.keyCode.ENTER) { // selecting proposition
+            $active.click();
+        } else { // navigation in propositions
+            var $to;
+            if (keycode === $.ui.keyCode.DOWN) {
+                $to = $active.nextAll('.o_mention_proposition').first();
+            } else if (keycode === $.ui.keyCode.UP) {
+                $to = $active.prevAll('.o_mention_proposition').first();
+            } else if (keycode === $.ui.keyCode.TAB) {
+                $to = $active.nextAll('.o_mention_proposition').first();
+                if (!$to.length) {
+                    $to = $active.prevAll('.o_mention_proposition').last();
+                }
+            }
+            if ($to && $to.length) {
+                $active.removeClass('active');
+                $to.addClass('active');
+            }
+        }
+    },
     _render_suggestions: function () {
         var suggestions = [];
         if (_.find(this.get('mention_suggestions'), _.isArray)) {
@@ -522,9 +530,10 @@ var BasicComposer = Widget.extend(chat_mixin, {
 
     on_keydown: function (event) {
         switch(event.which) {
-            // UP, DOWN: prevent moving cursor if navigation in mention propositions
+            // UP, DOWN, TAB: prevent moving cursor if navigation in mention propositions
             case $.ui.keyCode.UP:
             case $.ui.keyCode.DOWN:
+            case $.ui.keyCode.TAB:
                 if (this.mention_manager.is_open()) {
                     event.preventDefault();
                 }
@@ -560,12 +569,13 @@ var BasicComposer = Widget.extend(chat_mixin, {
                     this.trigger_up("escape_pressed");
                 }
                 break;
-            // ENTER, UP, DOWN: check if navigation in mention propositions
+            // ENTER, UP, DOWN, TAB: check if navigation in mention propositions
             case $.ui.keyCode.ENTER:
             case $.ui.keyCode.UP:
             case $.ui.keyCode.DOWN:
+            case $.ui.keyCode.TAB:
                 if (this.mention_manager.is_open()) {
-                    this.mention_manager.proposition_navigation(event.which);
+                    this.mention_manager._propositionNavigation(event.which);
                 }
                 break;
             // Otherwise, check if a mention is typed
@@ -814,7 +824,9 @@ var BasicComposer = Widget.extend(chat_mixin, {
      * @private
      */
     _onEmojiButtonFocusout: function () {
-        this._hideEmojisTimeout = setTimeout(this._hideEmojis.bind(this), 0);
+        if (this.$emojisContainer) {
+            this._hideEmojisTimeout = setTimeout(this._hideEmojis.bind(this), 0);
+        }
     },
     /**
      * Called when an emoji is focused -> @see _onEmojiButtonFocusout