If a Zabbix admin does a Full Clone of a template that contains a discovery element with trigger protypes already associated to host, any changes done on the new cloned template for the trigger prototypes are implemented on the host that the template was cloned from.

For example,
1.) Create a template named "Test_A" with discovery items and trigger prototypes. Wait until trigger prototypes are associated to the hosts.
2.) Do a "Full Clone" of template "Test_A" to a template called "Test_B".
3.) Now delete the trigger prototype out of template "Test_B" and you will see in details that the triggers are removed from hosts that are attached to template "Test_A".