Steps to reproduce:

*Followed all steps from https://git.zabbix.com/projects/ZBX/repos/zabbix/browse/templates/media/pushover*

1. In Admin > Media Types > token field updated.
2. In User settings > Media > added pushover send to 'usertoken'
3. Modified a ICMP latency trigger to lower limits to trigger an alert.

Result:
See screenshot. Verbose "No message defined for media type"

This is happening for all alerts from default templates too. So the plugin seems to have a bug.

Expected:
Pushover alerts received on device without error.