The display of a PDF document in the browser is handled differently in TruClient Firefox replay modes. In Interactive (Develop script) mode the content of the PDF document is displayed in the browser page. In Load mode replay the PDF content is not displayed. Instead a "Save as" dialog is shown.
The difference is caused by the different mimetypes.rdf file used in the interactive and load profiles for the script. The mimetypes.rdf used in load mode does not contain information about handling PDF files.