- Standard visibility removed; upgrade to advanced visibility and update plugin names (mysql→mysql8, postgres→postgres12).
- Deprecated several Worker Versioning APIs (UpdateWorkerBuildIdCompatibility, GetWorkerBuildIdCompatibility, GetWorkerTaskReachability) in favor of new versioning rules APIs.
- Performance and observability enhancements: MySQL query interpolation, shard‑info update tuning, OpenTelemetry env vars, matching task‑queue handover improvements, and new system search attributes (RootWorkflowId/RootRunId).