Missing image rendering feature in Grafana 8.5.21

Hello all,
i just updating Grafana to version 8.5.21 from 8.5.9 for security reason (CVE, etc) and in evaluating for using new Grafana alert engine (unified alerting).
the only thing missed only for image rendering, after we searching to the documentation (ref) it’s possible to implement it, but seems only for version 8.5.16 (ref). is this feature skipped in version 8.5.21 ?