Why can't you put a slash at the beginning of a menu link in Drupal?

Question

CMS

Hello!
Faced a strange problem. I created a menu in Drupal 7, everything seems to be fine, but the problem is that all links in it are written without a slash at the beginning, i.e. are relative to the current page. For example, node/add instead of the /node/add I need. Moreover, in the admin panel, Drupal does not allow me to put this slash manually - it says that the page was not found or I do not have access to it. Drupal is completely clean.
How to be? Maybe everything is solved by some setting? .. Help me figure it out, please. Thank you.

Answer 1

All links are absolute from the root.