Adding a node into a cluster wipes all the documents in default bucket

Basically adding in a data node to a cluster with a default bucket seems to wipe all the documents from the default bucket. You do not even need to rebalance in the server, just adding it is enough to trigger the bucket to be wiped.

Simple repro:
fresh 1 node cluster with kv,index,query services
create bucket (name it default)
add one document to default (can add as many as you'd like)
add a kv node into the cluster
before rebalance, check default bucket and it no longer has documents

This issue is not present in build 6.5.0-2910