diff --git a/addons/mail/static/src/js/discuss.js b/addons/mail/static/src/js/discuss.js
index 3b405761169..2142a21da4a 100644
--- a/addons/mail/static/src/js/discuss.js
+++ b/addons/mail/static/src/js/discuss.js
@@ -99,7 +99,7 @@ var PartnerInviteDialog = Dialog.extend({
                     self.do_notify(_t('New people'), notification);
                     // Clear the membersDeferred to fetch again the partner
                     // when getMentionPartnerSuggestions from the chatManager is triggered
-                    var channel = this.call('chat_manager', 'getChannel', self.channelID);
+                    var channel = self.call('chat_manager', 'getChannel', self.channelID);
                     delete channel.membersDeferred;
                 });
         }
@@ -508,7 +508,7 @@ var Discuss = Widget.extend(ControlPanelMixin, {
      */
     _selectMessage: function (messageID) {
         this.$el.addClass('o_mail_selection_mode');
-        var message = this._getMessage(messageID);
+        var message = this.call('chat_manager', 'getMessage', messageID);;
         this.selected_message = message;
         var subject = "Re: " + message.record_name;
         this.extendedComposer.set_subject(subject);
@@ -903,10 +903,10 @@ var Discuss = Widget.extend(ControlPanelMixin, {
         if (def) {
             def.then(function (value) {
                 if (value !== 'granted') {
-                    self._sendNotification(self, _t('Permission denied'),
+                    self.call('bus_service', 'sendNotification', self, _t('Permission denied'),
                         _t('Odoo will not have the permission to send native notifications on this device.'));
                 } else {
-                    self._sendNotification(self, _t('Permission granted'),
+                    self.call('bus_service', 'sendNotification', self, _t('Permission granted'),
                         _t('Odoo has now the permission to send you native notifications on this device.'));
                 }
             });
@@ -963,7 +963,7 @@ var Discuss = Widget.extend(ControlPanelMixin, {
      * @private
      */
     _onUnsubscribeButtonClicked: function () {
-        this._unsubscribe(this.channel);
+        this.call('chat_manager', 'unsubscribe', this.channel);
     },
 });
 
diff --git a/addons/mail/static/src/js/services/chat_manager.js b/addons/mail/static/src/js/services/chat_manager.js
index fb4b6672bc6..a58de02365a 100644
--- a/addons/mail/static/src/js/services/chat_manager.js
+++ b/addons/mail/static/src/js/services/chat_manager.js
@@ -352,7 +352,6 @@ var ChatManager =  AbstractService.extend({
      *              => list containing a list of members (cached by chat_manager)
      */
     getMentionPartnerSuggestions: function (channel) {
-        var self = this;
         if (!channel) {
             return this.mentionPartnerSuggestions;
         }
@@ -365,14 +364,7 @@ var ChatManager =  AbstractService.extend({
                     shadow: true
                 })
                 .then(function (members) {
-                    var suggestions = [];
-                    _.each(self.mentionPartnerSuggestions, function (partners) {
-                        suggestions.push(_.filter(partners, function (partner) {
-                            return !_.findWhere(members, { id: partner.id });
-                        }));
-                    });
-
-                    return [suggestions];
+                    return [members];
                 });
         }
         return channel.membersDeferred;
@@ -1642,7 +1634,7 @@ var ChatManager =  AbstractService.extend({
             web_client.set_title_part("_chat", tabTitle);
         }
 
-        this._sendNotification(web_client, title, content);
+        this.call('bus_service', 'sendNotification', web_client, title, content);
     },
     /**
      * Removes channel
diff --git a/addons/mail/static/src/js/services/chat_window_manager.js b/addons/mail/static/src/js/services/chat_window_manager.js
index bab6fbf7729..bea6eaf0ace 100644
--- a/addons/mail/static/src/js/services/chat_window_manager.js
+++ b/addons/mail/static/src/js/services/chat_window_manager.js
@@ -387,8 +387,8 @@ var ChatWindowManager =  AbstractService.extend({
         this.displayState.hiddenSessions = hiddenSessions;
         this.displayState.hiddenUnreadCounter = hiddenUnreadCounter;
 
-        if (this.displayState.$hidden_windows_dropdown) {
-            this.displayState.$hidden_windows_dropdown.remove();
+        if (this.displayState.$hiddenWindowsDropdown) {
+            this.displayState.$hiddenWindowsDropdown.remove();
         }
         if (hiddenSessions.length) {
             this.displayState.$hiddenWindowsDropdown = this._renderHiddenSessionsDropdown();
@@ -487,8 +487,8 @@ var ChatWindowManager =  AbstractService.extend({
                 self.displayState.hiddenUnreadCounter += session.window.unread_msgs;
             }
         });
-        if (self.displayState.$hidden_windows_dropdown) {
-            self.displayState.$hidden_windows_dropdown.html(self.renderHiddenSessionsDropdown().html());
+        if (self.displayState.$hiddenWindowsDropdown) {
+            self.displayState.$hiddenWindowsDropdown.html(self._renderHiddenSessionsDropdown().html());
             self._repositionHiddenSessionsDropdown();
         }
     },
diff --git a/addons/mail/static/tests/chatter_tests.js b/addons/mail/static/tests/chatter_tests.js
index 4ef63b70615..e247c01430a 100644
--- a/addons/mail/static/tests/chatter_tests.js
+++ b/addons/mail/static/tests/chatter_tests.js
@@ -369,6 +369,8 @@ QUnit.test('kanban activity widget with an activity', function (assert) {
 QUnit.test('chatter: post, receive and star messages', function (assert) {
     var done = assert.async();
     assert.expect(28);
+    
+    testUtils.patchWindowGetSelection();
 
     var bus = new Bus();
     var BusService = createBusService(bus);
@@ -533,7 +535,11 @@ QUnit.test('chatter: post, receive and star messages', function (assert) {
             assert.strictEqual($(".o_composer_input a").length, 1, "mention is 'green' in edit mode");
 
             BasicComposer.prototype.MENTION_THROTTLE = mentionThrottle;
+
+            //cleanup
             form.destroy();
+            testUtils.unpatchWindowGetSelection();
+            
             done();
         });
 });
diff --git a/addons/mail/static/tests/discuss_mobile_tests.js b/addons/mail/static/tests/discuss_mobile_tests.js
index 4e96c87f512..d17364b53ad 100644
--- a/addons/mail/static/tests/discuss_mobile_tests.js
+++ b/addons/mail/static/tests/discuss_mobile_tests.js
@@ -29,21 +29,13 @@ QUnit.test('mobile basic rendering', function (assert) {
     assert.expect(9);
     var done = assert.async();
 
-    var discuss = createDiscuss({
+    createDiscuss({
         id: 1,
         context: {},
         params: {},
         data: this.data,
         services: this.services,
-        mockRPC: function (route, args) {
-            if (args.method === 'message_fetch') {
-                return $.when([]);
-            }
-            return this._super.apply(this, arguments);
-        },
-    });
-
-    discuss.call('chat_manager', 'isReady').then(function () {
+    }).then(function (discuss) {
         // test basic rendering in mobile
         assert.strictEqual(discuss.$('.o_mail_chat_mobile_control_panel').length, 1,
             "should have rendered a control panel");
diff --git a/addons/mail/static/tests/discuss_tests.js b/addons/mail/static/tests/discuss_tests.js
index 7f48e3b0450..348a6357b5d 100644
--- a/addons/mail/static/tests/discuss_tests.js
+++ b/addons/mail/static/tests/discuss_tests.js
@@ -1,12 +1,18 @@
 odoo.define('mail.discuss_test', function (require) {
 "use strict";
 
-var testUtils = require('web.test_utils');
-var Widget = require('web.Widget');
-
+var ChatManager = require('mail.ChatManager');
+var Composers = require('mail.composer');
 var mailTestUtils = require('mail.testUtils');
 
+var concurrency = require('web.concurrency');
+var testUtils = require('web.test_utils');
+
+var BasicComposer = Composers.BasicComposer;
+var createBusService = mailTestUtils.createBusService;
 var createDiscuss = mailTestUtils.createDiscuss;
+var patchWindowGetSelection = testUtils.patchWindowGetSelection;
+var unpatchWindowGetSelection = testUtils.unpatchWindowGetSelection;
 
 QUnit.module('mail', {}, function () {
 
@@ -17,57 +23,125 @@ QUnit.module('Discuss client action', {
                 fields: {},
             },
         };
+        this.services = [ChatManager, createBusService()];
     },
 });
 
-QUnit.skip('mobile basic rendering', function (assert) {
-    // Unfortunately, this test is skipped for now because there is no way to
-    // execute the whole test suite in mobile (it only works test by test), so
-    // as the client action include for mobile is rejected when we are not in
-    // mobile, it isn't possible to test it
-    // Moreover, RPCs done by the chat_manager (e.g. message_fetch) should be
-    // properly mocked.
-    assert.expect(11);
+QUnit.test('basic rendering', function (assert) {
+    assert.expect(5);
+    var done = assert.async();
 
-    var parent = new Widget();
-    testUtils.addMockEnvironment(parent, {
-        data: this.data,
-        archs: {
-            'mail.message,false,search': '<search/>',
-        },
-        config: {device: {isMobile: true}},
-    });
-
-    var params = {
+    createDiscuss({
         id: 1,
         context: {},
         params: {},
+        data: this.data,
+        services: this.services,
+    })
+    .then(function (discuss) {
+        // test basic rendering
+        var $sidebar = discuss.$('.o_mail_chat_sidebar');
+        assert.strictEqual($sidebar.length, 1,
+            "should have rendered a sidebar");
+
+        var $nocontent = discuss.$('.o_mail_chat_content');
+        assert.strictEqual($nocontent.length, 1,
+            "should have rendered the content");
+        assert.strictEqual($nocontent.find('.o_mail_no_content').length, 1,
+            "should display no content message");
+
+        var $inbox = $sidebar.find('.o_mail_chat_channel_item[data-channel-id=channel_inbox]');
+        assert.strictEqual($inbox.length, 1,
+            "should have the channel item 'channel_inbox' in the sidebar");
+
+        var $starred = $sidebar.find('.o_mail_chat_channel_item[data-channel-id=channel_starred]');
+        assert.strictEqual($starred.length, 1,
+            "should have the channel item 'channel_starred' in the sidebar");
+        discuss.destroy();
+        done();
+    });
+});
+
+QUnit.test('@ mention in channel', function (assert) {
+    assert.expect(9);
+    var done = assert.async();
+
+    this.data.initMessaging = {
+        channel_slots: {
+            channel_channel: [{
+                id: 1,
+                channel_type: "channel",
+                name: "general",
+            }],
+        },
     };
-    var discuss = createDiscuss(params);
 
-    // test basic rendering in mobile
-    assert.equal(discuss.$(".o_mail_chat_mobile_control_panel").length, 1, "Mobile control panel created");
-    assert.equal(discuss.$(".o_mail_mobile_tab").length, 4, "Four mobile tabs created");
-    assert.equal(discuss.$('.o_mail_chat_content').length, 1, "One default chat content pane created");
-    assert.equal(discuss.$(".o_mail_chat_tab_pane").length, 3, "Three mobile tab panes created");
+    // Remove the mention throttle to speed up the test
+    var mentionThrottle = BasicComposer.prototype.MENTION_THROTTLE;
+    BasicComposer.prototype.MENTION_THROTTLE = 1;
 
-    // Inbox
-    assert.equal(discuss.activeMobileTab, "channel_inbox", "'channel_inbox' is default active tab");
-    assert.ok(discuss.$(".o_channel_inbox_item:nth(0)").hasClass("btn-primary"), "Showing 'Inbox'");
+    var fetchListenersDef = $.Deferred();
 
-    // Starred
-    discuss.$(".o_channel_inbox_item[data-type='channel_starred']").click();
-    assert.ok(discuss.$(".o_channel_inbox_item:nth(1)").hasClass("btn-primary"), "Clicked on 'Starred'");
+    createDiscuss({
+        id: 1,
+        context: {},
+        params: {},
+        data: this.data,
+        services: this.services,
+        mockRPC: function (route, args) {
+            if (args.method === 'channel_fetch_listeners') {
+                fetchListenersDef.resolve();
+                return $.when([ { id: 2, name: 'TestUser'} ]);
+            }
+            return this._super.apply(this, arguments);
+        },
+    })
+    .then(function (discuss) {
+        var $general = discuss.$('.o_mail_chat_sidebar')
+                        .find('.o_mail_chat_channel_item[data-channel-id=1]');
+        assert.strictEqual($general.length, 1,
+            "should have the channel item with id 1");
+        assert.strictEqual($general.attr('title'), 'general',
+            "should have the title 'general'");
 
-    assert.ok(discuss.$(".o_mail_chat_content").is(":visible"), "Default main content pane visible");
+        // click on general
+        $general.click();
+        var $input = discuss.$('.o_composer_input').first();
+        assert.ok($input.length, "should display a composer input");
 
-    discuss.$(".o_mail_mobile_tab[data-type='dm']").click();
-    assert.equal(discuss.activeMobileTab, "dm", "After click on 'Conversation', is now active tab");
+        // Simulate '@' typed by user with mocked Window.getSelection
+        // Note: focus is needed in order to trigger rpc 'channel_fetch_listeners'
+        $input.focus();
+        $input.text("@");
+        patchWindowGetSelection();
+        $input.trigger('keyup');
 
-    assert.ok(!discuss.$(".o_mail_chat_content").is(":visible"), "none", "'Main' content pane is invisible");
-    assert.ok(discuss.$(".o_mail_chat_tab_pane:nth(0)").is(":visible"), "'Conversation' pane is visible");
+        fetchListenersDef
+            .then(concurrency.delay.bind(concurrency, 0))
+            .then(function () {
+                assert.strictEqual(discuss.$('.dropup.o_composer_mention_dropdown.open').length, 1,
+                "dropup menu for partner mentions should be open");
 
-    discuss.destroy();
+                var $mentionProposition = discuss.$('.o_mention_proposition');
+                assert.strictEqual($mentionProposition.length, 1,
+                    "should display one partner mention proposition");
+                assert.strictEqual($mentionProposition.data('id'), 2,
+                    "partner mention should link to the correct partner id");
+                assert.strictEqual($mentionProposition.find('.o_mention_name').text(), "TestUser",
+                    "partner mention should display the correct partner name");
+
+                $mentionProposition.click();
+                assert.strictEqual(discuss.$('.o_mention_proposition').length, 0,
+                    "should not have any partner mention proposition after clicking on it");
+                assert.strictEqual($input.find('a').text() , "@TestUser",
+                    "should have the correct mention link in the composer input");
+
+                BasicComposer.prototype.MENTION_THROTTLE = mentionThrottle;
+                unpatchWindowGetSelection();
+                discuss.destroy();
+                done();
+        });
+    });
 });
 
 });
diff --git a/addons/mail/static/tests/helpers/mock_server.js b/addons/mail/static/tests/helpers/mock_server.js
index 365b067b55a..a2aef300736 100644
--- a/addons/mail/static/tests/helpers/mock_server.js
+++ b/addons/mail/static/tests/helpers/mock_server.js
@@ -5,14 +5,23 @@ var MockServer = require('web.MockServer');
 
 MockServer.include({
     /**
+     * Param 'data' may have a key 'initMessaging' which contains
+     * a partial overwrite of the result from mockInitMessaging.
+     *
+     * Note: we must delete this key, so that this is not
+     * handled as a model definition.
+     *
      * @override
+     * @param {Object} [data.initMessaging] 
      */
-    _performRpc: function (route, args) {
-        if (route === '/mail/init_messaging') {
-            return $.when(this._mockInitMessaging(args));
+    init: function (data, options) {
+        if (data && data.initMessaging) {
+            this.initMessagingData = data.initMessaging;
+            delete data.initMessaging;
         }
-        return this._super(route, args);
+        this._super.apply(this, arguments);
     },
+
     /**
      * Simulate the '/mail/init_messaging' route
      *
@@ -20,7 +29,7 @@ MockServer.include({
      * @return {Object}
      */
     _mockInitMessaging: function () {
-        return {
+        return _.defaults(this.initMessagingData || {}, {
             'needaction_inbox_counter': 0,
             'starred_counter': 0,
             'channel_slots': [],
@@ -28,7 +37,19 @@ MockServer.include({
             'mention_partner_suggestions': [],
             'shortcodes': [],
             'menu_id': false,
-        };
+        });
+    },
+    /**
+     * @override
+     */
+    _performRpc: function (route, args) {
+        if (route === '/mail/init_messaging') {
+            return $.when(this._mockInitMessaging(args));
+        }
+        if (args.method === 'message_fetch') {
+            return $.when([]);
+        }
+        return this._super(route, args);
     },
 });
 
diff --git a/addons/mail/static/tests/helpers/test_utils.js b/addons/mail/static/tests/helpers/test_utils.js
index e0a8a0a13de..095da27be58 100644
--- a/addons/mail/static/tests/helpers/test_utils.js
+++ b/addons/mail/static/tests/helpers/test_utils.js
@@ -55,24 +55,31 @@ function createBusService(bus) {
     return BusService;
 }
 
+/**
+ * Create asynchronously a discuss widget.
+ * This is async due to chat_manager service that needs to be ready.
+ *
+ * @param {Object} params
+ * @return {$.Promise} resolved with the discuss widget
+ */
 function createDiscuss(params) {
     var Parent = Widget.extend({
         do_push_state: function () {},
     });
     var parent = new Parent();
-    testUtils.addMockEnvironment(parent, {
-        data: params.data,
+    testUtils.addMockEnvironment(parent, _.extend(params, {
         archs: {
             'mail.message,false,search': '<search/>',
         },
-        mockRPC: params.mockRPC,
-        services: params.services,
-    });
+    }));
     var discuss = new Discuss(parent, params);
     discuss.set_cp_bus(new Widget());
-    discuss.appendTo($('#qunit-fixture'));
+    var selector = params.debug ? 'body' : '#qunit-fixture';
+    discuss.appendTo($(selector));
 
-    return discuss;
+    return discuss.call('chat_manager', 'isReady').then(function () {
+        return discuss;
+    });
 }
 
 return {
diff --git a/addons/mail/views/mail_templates.xml b/addons/mail/views/mail_templates.xml
index 28d92c9e157..6769462d404 100644
--- a/addons/mail/views/mail_templates.xml
+++ b/addons/mail/views/mail_templates.xml
@@ -54,6 +54,8 @@
         <template id="qunit_mobile_suite" name="mail_mobile_tests" inherit_id="web.qunit_mobile_suite">
             <xpath expr="//t[@t-set='head']" position="inside">
                 <script type="text/javascript" src="/mail/static/tests/discuss_mobile_tests.js"></script>
+                <script type="text/javascript" src="/mail/static/tests/helpers/mock_server.js"></script>
+                <script type="text/javascript" src="/mail/static/tests/helpers/test_utils.js"></script>
             </xpath>
         </template>
 
diff --git a/addons/web/static/tests/helpers/test_utils.js b/addons/web/static/tests/helpers/test_utils.js
index a4f6531d075..6f3b3ef4549 100644
--- a/addons/web/static/tests/helpers/test_utils.js
+++ b/addons/web/static/tests/helpers/test_utils.js
@@ -23,6 +23,8 @@ var Widget = require('web.Widget');
 
 var DebouncedField = basic_fields.DebouncedField;
 
+var originalWindowGetSelection; // cached replaced originalGetSelection
+
 /**
  * intercepts an event bubbling up the widget hierarchy. The event intercepted
  * must be a "custom event", i.e. an event generated by the method 'trigger_up'.
@@ -725,6 +727,50 @@ function patch (target, props) {
         });
     }
 }
+/**
+ * In Phantomjs, there is a crash when calling window.getSelection
+ * in order for the tests to work, for the specific test that uses it, replace
+ * the default window.getSelection by a mock
+ * 
+ * usage:
+ *     QUnit.test('...',function(done){
+ *          testUtils.patchWindowGetSelection();
+ *          
+ *          // do something that needs to use window.getSelection()
+ *          assert.strictEqual(....);
+ *          
+ *          // restore the original function
+ *          testUtils.unpatchWindowGetSelection();
+ *      
+ *          // finish the test
+ *          done();
+ *     })
+ */
+
+function patchWindowGetSelection() {
+    originalWindowGetSelection = window.getSelection;
+    window.getSelection = function () {
+        return {
+            removeAllRanges: function () {},
+            addRange: function (range) {},
+            getRangeAt: function (index) {
+                return {
+                    startOffset : 0
+                };
+            },
+            anchorNode: {
+                parentNode: {
+                    childNodes: [{
+                        outerHTML: "@",
+                        nodeType: 3,
+                        textContent: '@',
+                    }],
+                },
+            },
+        };
+    };
+}
+
 /**
  * Unpatches a given Class or Object.
  *
@@ -749,6 +795,14 @@ function unpatch(target) {
     delete target.__patchID;
 }
 
+/**
+ * after using patchWindowGetSelection, at the end of your test
+ * you must restore the default function so there is no impact to the other tests
+ */
+function unpatchWindowGetSelection() {
+    window.getSelection = originalWindowGetSelection;
+}
+
 // Loading static files cannot be properly simulated when their real content is
 // really needed. This is the case for static XML files so we load them here,
 // before starting the qunit test suite.
@@ -775,11 +829,13 @@ return $.when(
         intercept: intercept,
         observe: observe,
         patch: patch,
+        patchWindowGetSelection: patchWindowGetSelection,
         removeSrcAttribute: removeSrcAttribute,
         triggerKeypressEvent: triggerKeypressEvent,
         triggerMouseEvent: triggerMouseEvent,
         triggerPositionalMouseEvent: triggerPositionalMouseEvent,
         unpatch: unpatch,
+        unpatchWindowGetSelection: unpatchWindowGetSelection,
     };
 });