This does not solve the problem. You can not tell me this was not tested before it was sold, right?
What is the verdict?
The issue lies with your web code, not the extension. As Jason stated, PDF embedding in such manner is NOT standards compliant nor is it even permissible by many browsers. CSS Menu Writer, however, IS standards compliant. As a professional web coder, I can attest that it is CSS Menu Writer is correct and works exactly as it should. The reality is: even without the extension, a pro web designer would write the menu code in the exact same manner that the extension generates.
As a web coder, I would ask why do you want to embed a PDF in such a manner? Have you thought about alternatives to that like perhaps creating an image of the PDF first, then displaying the image and create a link from the image that would download the actual PDF? That would be the correct method by web standards.