I recently updated to Firefox 18 and since that time, the latest version of Schubert PDF Browser Plugin does not work
Make sure that plugin is enabled.
We have received numerous reports from our customers using Firefox 18 for Mac that the Schubert PDF Browser Plugin does not work.
If Firefox has a PDF viewer built in then it doesn't appear to be working in Firefox 18 for Mac. Our users are complaining that they are simply being shown the file path of our DLL and not the PDF that streams as an application/PDF from that DLL.
They may be using some content or ad blocking extensions if they do not get the file.
I assume that the DLL runs server side and is used to retrieve a specific document.
Checking the server logs should confirm that you get a request to retrieve a non existing file.