UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/53.0.2785.143 Chrome/53.0.2785.143 Safari/537.36

Example URL:

Steps to reproduce the problem:
1. go to https://webrtc.github.io/samples/src/content/getusermedia/record/
2. record a call that is ~2 minutes long
3. download the file
4. play the file in chrome

What is the expected behavior?
You can seek in the file while playing.

What went wrong?
Seeking does not work.

Did this work before? N/A 

Is it a problem with Flash or HTML5? HTML5

Does this work in other browsers? Yes

Chrome version: 53.0.2785.143  Channel: n/a
OS Version: 
Flash Version: Shockwave Flash 16.0 r0

Contents of chrome://gpu: 

This makes MediaStreamRecorder less awesome than it could be.

There is metadata missing apparently. Firefox 47+ can still playback + seek, see https://bugzilla.mozilla.org/show_bug.cgi?id=657791

I'd be fine if it worked when not setting duration (see 567859) if modifying the resulting blob is easier.