I sell Digital magazines online, it’s PDF and browsers tend to open those in a window. The issue is twofold, it not only show the ultimate link of the file, many have no idea that they can download the files. So here’s how to force download a PDF file on Amazon S3
Click on the PDF file (the filename itself)
On the right, look at the metadata tab
Click on Add metadata
Select Content-Disposition > Attachment, voilà!
Rince and repeat