Reproduce:
Hosts -> All Hosts
Click a host
Click the 'Hosts' breadcrumb link

Expected:
User is taken to all hosts index page

Actual:
Nothing happens, the link goes to the current host with a trailing octothorpe (i.e. https://foreman/hosts/centos7-katello-client.virbr0.akofink-desktop#)

Seen in Katello nightly; I haven't tested if this is an issue in Foreman without Katello.