Download Videos
- Right-click on the video, then select the third option Show video URL
- Copy the video URL from the little box.
- Change web or www to mbasic as shown below then press Enter on your keyboard to redirect it to the basic mobile version of Facebook.
- Right click on video and click "Save As"
Ref: https://www.tutovids.net/how-to-download-facebook-videos-without-any-software/