anchor.diff:  
  -
  -<!-- This tabbed_files_border id used by run_tests.js.rjs to colour -->
  -<!-- the tabbed_files editArea border red or green as appropriate.  -->
  -<table cellpadding="0" cellpadding="0">
  +<table cellpadding="0" 
  +       cellpadding="0">
     <tr valign="top">
       <td class="file-manager panel">
  -
         <table>
           <tr>
             <td>
              <div id="shown_increment_number">
  -             <span class="increment-box" title="current increment"-%>
  +             <span class="increment-box" 
  +                   title="current increment"-%>
                  <%= @shown_increment_number -%>
                </span>
              </div>
  
positive.code:   </tr>
  </table>
  
  
  <div class="hidden">
  
    <!-- When run-tests is clicked the javascript preRunTests() function copies  -->
    <!-- the contents of each editArea tab back to its hidden textarea (below)   -->
    <!-- before submitting the form. On the server rails grabs the file contents -->
    <!-- from these hidden textareas and not from the tabbed_files editArea.     -->
    <% @manifest[:visible_files].each do |filename,file| -%>
      <!-- This outer div is needed for run_tests_outcome from run_tests.js.rjs -->
      <div id="<%=filename-%>_div">
        <textarea id="<%=filename-%>" 
                  name="<%=filename-%>"><%= h file[:content] -%></textarea> 
        <% file.delete :content -%>
      </div>
    <% end -%>
  
    <div id="manifest.rb_div">
        <textarea id="manifest.rb_div" 
  
negative.code:           </tr>
  		<% end -%>
  	  </table>
      </td>
  
      <td>
        <!-- EditArea turns this textarea into a tabbed edtitor. See _javascript.html.erb -->
        <table cellpadding="7" 
               id="tabbed_files_border" 
               class="<%=@outcome-%>">
  