app/views/attachment_masks/wait.html.erb
<% @title = _('Attachment processing...') %>
<h1><%= @title %></h1>
<p>
<%= _('We don\'t have this attachment in our cache at present, we are now ' \
'processing your request and this page will reload once the ' \
'attachment is available.') %>
</p>
<% content_for :javascript_head do %>
<meta http-equiv="refresh" content="2">
<% end%>