fix

@@ -177,6 +177,8 @@ var chat = {
                 self.canManualService && self.switchService('human');
             })
             .on('keydown.chat.sendText', '.text-in', function(event) {
+                document.body.scrollTop = document.body.scrollHeight;
+
                 if (event.which === 13) {
                     let val = $.trim(event.target.value);