Group + collapse query doubt

[Angad Sharma]

I use solr 7.1 in production right now. We use group
query to group on "query _type" field, and collapse on
"real _id" field so that we get unique real_ids in each
group (nullPolicy: expand).
I want to migrate to solr 9 but seems like using
collapse with group is deprecated. How can I
replicate the same usecase without impacting
performance/latency?