Heapster

Previous to version 4, the documentation for Openshift referenced Heapster for obtaining metrics on resource usage of pods, such as in this documentation:

https://docs.openshift.com/container-platform/3.11/dev_guide/pod_autoscaling.html

In researching Heapster, I see that it may have been deprecated:

https://github.com/kubernetes-retired/heapster

I do see that references to it have been somewhat removed from later documentation, such as this:

https://docs.openshift.com/container-platform/4.1/nodes/pods/nodes-pods-autoscaling.html

Has Heapster been replaced with something that is still maintained? Or has Red Hat taken to ensuring its properly supported (secure, functional) for version 4 and beyond?