Rails: notice: messages won't disappear Using rails_layout gem?

Question

I'm not sure if this is a bug or what, but the notice messages are not disappearing and I have looked at a bunch of other examples, none of them explain my case: like these: Why flash message won't disappear?

rails 4 -- flash notice

Rails flash notice won't go away in Safari?

devise gem flash messages

I used the Rails_Composer and I promised myself not to use it again, because it just caused me a nightmare

This is what I have loaded in my files:

application.js

//= require jquery
//= require jquery_ujs
//= require bootstrap
//= require wiselinks
//= require_tree .

application.css.scss

/*
 *= require_tree .
 *= require_self
 */
framework_and_overrides.css.scss
@import "bootstrap.min";

and as the Rails_Composer generates the files, this is what we have in the layout:

_messages.html.eb

<%# Rails flash messages styled for Bootstrap 3.0 %>
<% flash.each do |name, msg| %>
  <% if msg.is_a?(String) %>
    <div class="alert alert-<%= name.to_s == 'notice' ? 'success' : 'danger' %>">
      <button type="button" class="close" data-dismiss="alert" aria-hidden="true">&times;</button>
      <%= content_tag :div, msg, :id => "flash_#{name}" %>
    </div>
  <% end %>
<% end %>

any idea how to fix this mess ?