We got a report from a customer about the openstack template, they weren't able to use it due to login issues, they were receiving error:
"Failed to parse response received from OpenStack Identity API. Check debug log for more information."
But after they changed "X-Subject-Token" in the template to lowercase "x-subject-token" it started to work.
On line 96: https://git.zabbix.com/projects/ZBX/repos/zabbix/browse/templates/cloud/openstack/template_cloud_openstack_http.yaml?at=release%2F6.4#96