Cannot Access NPAPI Functions In Firefox Extension

I'm having trouble getting an NPAPI plugin to load in a Firefox Extension. The way I'm doing it now is the plugin is already registered in Windows, so I load an embed element via a

Solution 1:

There is no <embed> tag in XUL, you mean to use the HTML <embed> tag. Use the HTML namespace for this tag:

<embed xmlns="http://www.w3.org/1999/xhtml" ...></embed>

Additional information: https://developer.mozilla.org/en/Namespaces