Chrome sends two requests when downloading a PDF (and cancels one of them)

Question

I noticed that whenever you download a PDF in Chrome, it consistently makes two requests, and then cancels one of them. This is causing the request to be registered twice in

Answer 1

I had the same problem in an iframe. I turned of the PDF Viewer extension and the problem disappeared. I'm thinking the extension downloads the file twice. The first time to get the size, the second time to download with a progress bar (using the size gathered in the first request)