UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.75 Safari/537.36

Example URL:
http://www.mazedudemusic.com/download.php?file=Mzd-SlamDavis.mp3

Steps to reproduce the problem:
1. Find a website to which you can't maintain a stable TCP connection. E.g. right now my ISP is Netvigator in Hong Kong and it's experiencing some serious connectivity issues with SoundCloud's CDN, which seems to be located in California.
2. Start to download a large enough file from that website.
3. Wait.

What is the expected behavior?
Chrome would correctly flag the download as incomplete e.g. with a "Failed - Network Error" message.

What went wrong?
Chrome *sometimes* pretends the download has completed successfully, with no error message whatsoever, even though it has managed to download only part of it.

Did this work before? N/A 

Chrome version: 49.0.2623.75  Channel: stable
OS Version: OS X 10.11.3
Flash Version: Shockwave Flash 20.0 r0

I started noticing this behaviour since Chrome 48. I'm not sure if previous versions of Chrome were affected. Which also means I don't know how many of my downloads were silently corrupted because of this behaviour (because, you know, most websites don't provide checksums or .asc files).

This is a pretty serious issue. There is no reason Chrome shouldn't be able to detect an incomplete download, since the initial HTTP response header contains the size of the payload.

Note that this doesn't *always* happen - sometimes Chrome does correctly flag the download as failed. So you may need to retry a few times.
 

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