! THE Live Stream downloader WORKS JUST FINE !
I use this addon for it's video grabbing part. :)

Guys, hover the Turbo Download Manager and you'll see a busy addon. The video files may not show up in the Downloads folder (or whereever your d/l files are stored) instantly - just be patient! The addon works in the background.

To get started choose "Extract Media Links" from the dropdown menu that you get after right clicking in the tab with the desired video.
Sometimes you have to pick the right resolution - try all if offered until you have the right video (*.ts). Use "Download Link(s)" instead of "merge"… When it's done you have a lot of files in the download location - carefully delete all but the biggest of the new files (usually the video).
Web developers really try to make it hard to download contet you'd like to see/hear offline. A few times you can not download the right file…
However, it's great that this addon exists!

Regarding the user interface:
I find the popup window (when you click on the "Turbo Download Manager" icon in the toolbar) a bit minimalistic, e.g. how do you open another connection to add/handle another segment of a file that is downloaded?
When you did "PAUSE" a download then a click on the icon (toolbar) does show the oldest downloaded file on the top. To resume you have to scroll very down in order to reach the "RESUME" button.
It would be nice to have a "dark mode" option…