How can HTML5

  html5, question

In theory, videos loaded through the video tag can be downloaded directly, and the video address will appear in the code, but how does YouTube prevent users from downloading directly? Hide video address? Or is it some server-side function?

https://www.youtube.com/watch?  v=ShLTI5xgoFA&spf=navigate

If there is no mistake, Youtube should use such an api to obtain information. src in dom inside is only an interface.