1) Right-click → View frame source on the video frame
2) In the new tab that opens, press F3 and put in the search .mp4
3) Find the last one in the search and select the link that starts from this ending and is in ""
4) We do pasting the link in a new tab and press the three dots at the bottom right and select download.
In case it does not work, then we do the same procedure for the immediately preceding link.
The reason for not displaying the video with choice download is because the video resolution of the link must be equal to or lower than the one they uploaded it to.