How to fix render-blocking video resource download on Safari

This is related to the ```MOOV``` atom that contains all the metadata and information about the frame locations other important information the browser needs to know about the video. For some reason, all other major browsers load it with no issues but Safari prefers to wait until the whole resource has downloaded in order to decide what to do with it. 

For ```mp4``` files, downloading FFMPEG and running the following command solved my issue: 

```
./ffmpeg -y -i source.mp4 -movflags faststart dest.mp4
```

What it does is that it takes the ```MOOV``` atom from the end and adds it right at the start.

nickciolpan
19 Jul 2020