Exception in Explain API: async actions are left after rewrite

[spinscale]

Elasticsearch version (bin/elasticsearch --version): 7.9.3

Steps to reproduce:

DELETE social-network

PUT social-network/_doc/data?refresh
{
  "key":"value"
}

GET social-network/_doc/data/_explain
{
  "query": {
    "bool": {
      "should": [
        {
          "terms": {
            "_id": {
              "index": "social-network",
              "id": "non-existent",
              "path": "does-not-matter"
            }
          }
        }
      ]
    }
  }
}

returns

# GET social-network/_doc/data/_explain
{
  "error" : {
    "root_cause" : [
      {
        "type" : "query_shard_exception",
        "reason" : "failed to create query: async actions are left after rewrite",
        "index_uuid" : "p5QUbQQySzagagpW9_Lf6w",
        "index" : "social-network"
      }
    ],
    "type" : "query_shard_exception",
    "reason" : "failed to create query: async actions are left after rewrite",
    "index_uuid" : "p5QUbQQySzagagpW9_Lf6w",
    "index" : "social-network",
    "caused_by" : {
      "type" : "illegal_state_exception",
      "reason" : "async actions are left after rewrite"
    }
  },
  "status" : 400
}

[elasticmachine]

Pinging @elastic/es-search (:Search/Search)

[chmchmchm]

Hey, did this ever get fixed or is there a workaround?

[dlants]

Still running into this on v8.1

[dlants]

Possibly a similar issue as #29033 ?