Is it good to use "//" instead of http/https?

Question

Browsers

I noticed a long time ago that Google switched to using two slashes instead of explicitly specifying protocols. I’m thinking of switching to them too, but I’m tormented by the question of cross-browser compatibility and support for old browsers: is this an old feature, do all browsers support such abbreviations as IE does, can old devices with their browsers be friends with slashes as well?

Answer 1

Yes, this is good, this is an ancient feature, the browser chooses the same protocol as the page from which the link is followed.

Answer 2

I don’t specify the protocol at all, and I don’t enter slashes, just like www)))

Answer 3

okay what's the difference how to write the main thing that would work and sink)