Markup action attribute does not seem to work for replace

Description:

In freemaker when using the tag markup with attribute action="replace" ie

<@markup id="custom-upload-dependencies" target="js" action="replace" scope="global">

The action is not respected.

Steps to reproduce:

• Install the latest alfresco 4.2 enteprise
• copy the files dnd-upload-blacklisted.js & dnd-upload.get.html.ftl to the folder tomcat/webapps/share/WEB-INF/classes/alfresco/site-webscripts/com/myco/upload-blacklist/components/upload
  and the file upload-blacklist-module.xml to the folder tomcat/webapps/share/WEB-INF/classes/alfresco/site-data/extensions. (all files attached to this jira)
• Start alfresco
• Login to alfresco share using chrome as the browser and click on the "Repository" link in the menu bar
• Once the page loads in chrome open the developer tools (Menu>Tools>Developer tools)
• On the developers tools click on the "Elements" tab and search for dnd-upload

Expected Behavior:

One entry with the replaced javascript should be listed ie

<script type="text/javascript" src="/share/res/myco/modules/uploadBlacklist/dnd-upload-blacklisted.js"></script>

Observed Behavior:

Two dnd-upload javascript files are listed

<script type="text/javascript" src="/share/res/myco/modules/uploadBlacklist/dnd-upload-blacklisted.js"></script>
<script type="text/javascript" src="/share/res/components/upload/dnd-upload_59f8323c54d581115e1b1f40356a3bd9.js"></script>

Analysis to date:

Tried changing the action to "before", "after" and "notworking" to verify their behaviors, with before the upload-blacklisted javascript appears before the original upload javascript as expected. With after the upload-blacklisted javascript appears after the original upload javascript, with "notworking" the upload-blacklisted javascript does not appear at all but hte original upload javascript file does so it appears that these work as expected.