Alert tuning for Custom detection rules

We’re trying to set up an alert tuning rule for some of our custom detection alerts. The rule itself is straightforward: it should automatically resolve alerts based on the alert name and a few additional conditions. However, it doesn’t seem to work.

I came across this thread: Alert Tuning (formerly Alert Suppression) Issues | Microsoft Community Hub.

Unfortunately, the article linked there doesn’t mention anything about custom detections.

Does anyone know whether alert tuning still doesn’t support custom detection alerts?