This method will get the video and its audio AS SEPARATE FILES. The downloaded video will have no sound, but you will be able to download its audio file and connect it to the video in some video editing program if you need to. In Google Chrome, go to Facebook. Open the Chrome Developer Tools (F12). Go to the Network tab in the Developer Tools (it’s at the top of the Developer Tools window …
https://stackoverflow.com/questions/48843356/decoding-facebooks-blob-video-url

