Why is creating a link in ISPmanager buggy?

Question

ISPmanager

CentOS, ISPmanager pro...
In the file manager I try to create a link, in the "Value" field I write: /var/www
When I follow the link - in the address (above the list of files) - everything is OK (i.e. "/var/www "). But as soon as you switch to any user, an extra slash appears in the address: "/var/www/ / user1" and is saved when deepening ...
If you switch manually, i.e. not by reference, then everything is fine, no extra slash. And the problem is that because of this glitch - archives are not created, for example, by means of a file manager.
Question: what am I doing wrong / as it should be?