Video DownloadHelper shows error: Failed downloading media manifest

I have usually found the Video DownloadHelper extension for Firefox reliable--at least, any hiccups have usually been solved by upgrades to the extension or to Firefox itself.

For the last week any download I attempt seems to progress satisfactorily, until at the end (or what I think is the end) it shows the error message "Failed downloading media manifest"

I am running Linux Mint Cinnamon 19 on a Lenovo ThinkCentre with Firefox 72.0.1. I installed Video DownloadHelper on Chromium, but with the same results.

Have many other people run into this problem, and has anyone found a solution, or is just a matter of waiting for the next round of updates?

Or is there a better (for the moment) downloader for shows and movies?

Thanks!