To get started, log into your Facebook account if needed, then find the Facebook video which you want to download.

Right-click on the Date/Time stamp above the video post, then select Copy link address from the drop-down menu.

Next, go to your browser, open a new tab, then paste the copied video link in the address bar.

Change www or web at the beginning of the url to mbasic as shown below then press Enter on your keyboard to redirect it to the basic mobile version of Facebook.

Once here, click on the the video to open it in a new window.

While it's playing, right-click on it and select Save Video As...

Finally, give your video a name if you want, then choose a destination where to save it and press the Save button.

Open the Facebook app and log into your account, if you haven't logged in already.

Find the Facebook video that you want to download, then tap the three-dot icon at to the top right of the video post and select Copy link.

Now, open a browser app (Google Chrome) and paste the copied video link in the address bar.

Next, change www or m to mbasic as shown below and tap Go.

Log into your Facebook account, if prompted to do so.

Now, tab on the video to open it in a new window.

Tap the three-dot icon at the bottom right corner of the video player or long-press on the video until you see the Download video option, then tap on it to start downloading the video.

Once the download is finished, click Open at the bottom to view the video or check the Downloads folder.