How does LI RU get where the user came from?

Question

PHP

I broke my head, I can’t understand how the liveinternet counter counts where the user came from
counter link counter.yadro.ru/hit?q;t17.6;r;s1920*1080*24;u;
through it, he receives HTTP_REFERER - this is the page you went to (and where the counter itself started), but not from which you came,
but how to transfer where the user came from?

Answer 1

Open developer tools, network section.
Everything that is available to the counter must be indulged in one form or another.
A simple example - https://www.kaminskiy-web.com/stati/pishem-grafich...