I have a template "Template App HTTP Service" that is directly linked to hosts. Trying to add a dependency from that to "Template ICMP Ping" which is linked to hosts through other templates fails with:

Updated: Trigger "HTTP service is down on

{HOST.NAME}" on "Template App HTTP Service".
Updated: Trigger "HTTP service is down on {HOST.NAME}

" on "host-xxx".
Cannot add dependency from a host to a template.

I have similar template "Template App SSH Service" that is linked to hosts through "Template OS Linux" adding the same dependency there works.