Obtain the NUFORC link eg:

https://nuforc.org/sighting/?id=194812

Open in Firefox

Press F12 for the developer view

Switch to the Network tab

Filter by Media

Press play on the video you want

This will then start to show the media links in the developer view, the media links will repeat they are chunked but each will reference the source

The backend streaming service splits the audio stream so if you want the audio then you need to download it separately and remux later

Double clicking on the GET link (under Filter Headers) will open it and download it (depending on your browser settings)

No metadata will be present and the files are watermarked and so have been re-encoded, but these will be best quality available for a NUFORC sighting.

Thanks for this

There is another method I have used that involves using the VLC media player program. I can't say if it is any easier, or if the quality is different, but it will include the audio.

Similar to the above method, it starts on the the "Network" tab of Firefox's developer tools. When the video starts to play in the browser there should be a row just before all of the video and audio chunks where the file column is something like "dash.mpd?v=x" and the type column says "octet/stream". Right click on this row and "Copy Value" -> "Copy URL".

Then in VLC click the "media" menu in the toolbar, then "Convert/Save". Then select the "Network" tab, paste in the url from Firefox. On the next page I typically use "webm" as the file format. Provide a filename to save the file and then after clicking the "start" button VLC will download both the video and audio to the file location you specified.

Edit: looks like my method is downloading a low resolution version of the video unlike @jarlrmai 's method which gave me a higher rez video.