Thank you for your post.
Our Development and Testing departments are aware of this issue with Chrome not rendering some PDF files correctly, and this has been reported to Google. As stated on page 18 of the FileMaker 13 WebDirect Guide (https://fmhelp.filemaker.com/docs/13/en/fm13_webdirect_guide.pdf):
"Web browsers provide inconsistent support for media files, and browser versions may vary on different operating systems. Some browsers may not correctly insert, display, or play certain media files. For example, video files may play as audio files if the video file format is not supported by the browser or operating system."
One of our other Support Technicians (TSFalcon) alerted me to a similar post that may apply. See:
Let me know if this applies.
Thanks for your efforts.
SSL is not enabled, but the database ist accessed via VPN. When I enable unsafe scripts in Chrome, the PDFs are shown.