You are trying to reach http site (Zabbix API) from the https site (Grafana), which is by default blocked by your browser. Switch your Zabbix to https as well or try to use proxy access to the Zabbix (configure it in Zabbix datasource settings).
You are trying to reach http site (Zabbix API) from the https site (Grafana), which is by default blocked by your browser. Switch your Zabbix to https as well or try to use proxy access to the Zabbix (configure it in Zabbix datasource settings).