Using Firefox, open Developer Tools, go to the Network tab, reload the page, find the appropriate .m3u8 entry, right-click, Copy Value > Copy as cURL. Then paste the resulting cURL command into here: https://windyakin.github.io/curl2ffmpeg. Download and install the free, open source FFMpeg tool if you don't already have it, paste the resulting ffmpeg command into your commandline and enjoy the video!