A container field optimized for interactive content and into which "Insert PDF" was used to insert the PDF should work for you. If it doesn't, you should post this as a bug report over in Report an Issue.
Hey thank you for your reply
Insert pdf is greyed out. So I can't use that option. Right now we're using a drag and drop to insert documents into the container field.
The weird thing is, that I use the container field with a small size in a portal (also definded as interactive) and there i works perfectly. I have a script on that container field, to open up another layout based on the documents, to display the pdf bigger so you are able to read it inside FM. And there I don't see the document no more, I only see the reader icon of Windows 8.
I don't understand why it's working on one place and not on another.
I found a solution.
On my Windows 8 computer, Acrobat Reader wasn't installed. So I had to install Acrobat Reader, changed in the "default programs" settings .pdf to Acrobat Reader and I restarted the computer. Now it works like a charm.
Thank you for your help