Foreskinluv Stream downloader extensions are iffy. What you want to do is have VLC media player installed (who doesn’t at this point) and rip the stream directly. Load the video page and press F12, click the tab labelled “Network” and use the search box to find the .m3u8 file - might need to refresh the video page once you’ve got the network tab open, or start the video playback for it to show.
Anyways, find the M3U8 address, that’s a stream encoding file. Open VLC, click “Media”, select “Open Network Stream…”, copy-paste the M3U8 address from your browser into the VLC network URL box, click the dropdown on the “Play” button and select “Convert”. It should show a bunch of options you don’t need to tinker with, and a prompt to select a destination file location - that’s where the video will save, pick a name and location and click “Start” in that window, then play in the main VLC window.
You can probably find a better guide than my rambling if you google it, just search something like “how to get video from M3U8”. It’s a pain in the ass, but about the only 100% guaranteed way to save videos now.