Zend certified PHP/Magento developer

Why do I get a .ism link in stead of .mp4?

So basically my lectures are recorded and published on mediasite.com. I found a way to get a link so I can download all the lectures (I use Chrome btw):

  1. Play the video
  2. Inspect element
  3. Go to network
  4. Click on one of the updates and there it is (this is where I normally copy the link).

But sometimes, randomly, I get a link with .ism at the end and I can’t download it. So is there anyone who can help me pls?

Ps: I tried using an extension but the site is weird because it splits a 2 hour lecture into 8 second clips.