ControllerModal gets method for displaying inline alerts

app/assets/javascripts/app/controllers/_application_controller.coffee

@@ -602,6 +602,16 @@ class App.ControllerModal extends App.Controller
       return @formParam(@container.find('.modal form'))
     return @formParam(@$('.modal form'))
 
+  showAlert: (message, suffix = 'danger') ->
+    alert = $('<div>')
+      .addClass("alert alert--#{suffix}")
+      .text(message)
+
+    @$('.modal-alerts-container').html(alert)
+
+  clearAlerts: ->
+    @$('.modal-alerts-container').empty()
+
   localOnShow: (e) =>
     @onShow(e)
 
@@ -650,6 +660,7 @@ class App.ControllerModal extends App.Controller
   submit: (e) =>
     e.stopPropagation()
     e.preventDefault()
+    @clearAlerts()
     @onSubmit(e)
 
 class App.SessionMessage extends App.ControllerModal

app/assets/javascripts/app/views/modal.jst.eco

@@ -11,6 +11,7 @@
         <h1 class="modal-title"><% if @headPrefix: %><%- @T(@headPrefix) %>: <% end %><%- @T(@head) %></h1>
   <% end %>
       </div>
+      <div class="modal-alerts-container"></div>
       <div class="modal-body">
       <%- @content %>
       </div>

app/assets/stylesheets/zammad.scss

@@ -6516,6 +6516,10 @@ footer {
     opacity: 0.18;
   }
 
+  .modal-alerts-container {
+    padding: 0 23px;
+  }
+
   .modal-body {
     padding: 0 23px;