404 on git.rancher.io

Hi all,
I have a running k3s (v1.20.5+k3s1) cluster in HA with 3 master and 2 nodes.
When I go to Cluster Explorer → Apps I see the message “There are no charts available, have you added any repos?”.

The chart repositories are the default from k3s installation.
I tried to reach the url from the browser but the url is not found, 404 status code.

How i wrong?