As a user of an existing database not using MySQL GTIDs, I want to enable the feature in MySQL 8.0.23+ to assign anonymous transactions to a local GTID [or specific UUID] so that I can continuously replicate part of my database to Aiven.

The objective is to create a live read-only replica or replicas containing region-specific databases, plus shared search data. Initial data can be replicated from a MySQL 8 replica of the non-GTID database, but re-enabling replication from the upstream origin breaks Aiven replication, as anonymous transactions exist.