# install ffmpeg
sudo apt-get install ffmpeg

# get a link from a website (with developer tools); filter: ".m3u8"
# right click on the m3u8 link and copy link address (eg: http://someserver.com/somefile.m3u8)

# download to an mp4
ffmpeg -i "http://someserver.com/somefile.m3u8" -c copy myvideo.mp4