setCustomContext not showing data after upgrade from 7.9 to 8.1.2

[hertzden (Harshit Purwar)]

We have setup custom context to fetch session FCP data for all our apps, last month we upgraded elastic version from 7.9 to 8.1.2 on 11th April, 2022. Since that date we are not able to see data in console while running query.

This is our query:

GET _search
{
 

    "aggs": {
        "max_of_fcp_b": {
            "terms": {
                "field": "transaction.custom.session",
                "size": 10000000
            },
            "aggs": {
                "fcp_max": {
                    "max": {
                        "field": "transaction.marks.agent.firstContentfulPaint"
                    }
                }
            }
        },
        "percentiles_fcp": {
            "percentiles_bucket": {
                "buckets_path": "max_of_fcp_b>fcp_max",
                "percents": [
                    95.0
                ]
            }
        }
    },
    "size": 0,
    "stored_fields": [
        "*"
    ],
    "_source": {
        "excludes": [
            "sourcemap.sourcemap"
        ]
    },
    "query": {
        "bool": {
            "must": [],
            "filter": [
                {
                    "match_all": {}
                },
                {
                  "match_phrase": {
                    "service.name": "App Name"
                  }
                },
                {
                    "exists": {
                        "field": "transaction.marks.agent.firstContentfulPaint"
                    }
                },
                
                {
                    "range": {
                        "@timestamp": {
                            "gte": "2022-04-11T12:49:15.858Z",
                            "lte": "2022-05-04T12:49:15.858Z",
                            "format": "strict_date_optional_time"
                        }
                    }
                }
            ],
            "should": [],
            "must_not": []
        }
    }


}