groupPolicy property
GroupPolicy sets how group and thread rooms are admitted: "open", "allowlist" or "disabled". Empty leaves it unchanged.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
String? groupPolicy;