This message was deleted.

There maybe a better way but this will show you container images in all namespaces:

kubectl get pods -A -o jsonpath="{.items[*].spec['initContainers', 'containers'][*].image}" |\
tr -s '[[:space:]]' '\n' |\
sort |\
uniq -c

maybe helpful to look at all namespaces incase if there is nginx deployed with some app otherwise you can just look at kube-system

Its the prefix that is the upstream version