4.24.3, having this for a few assets, including maps.
UATHelper: Packaging (Windows (64-bit)): LogSavePackage: Warning: /Game/Run/Components/Spawn_System/Blueprints/Character/BP_Respawn_Point imported Serialize:/Engine/EditorMaterials/TargetIconSpawn, but it was never saved as an export.
PackagingResults: Warning: /Game/Run/Components/Spawn_System/Blueprints/Character/BP_Respawn_Point imported Serialize:/Engine/EditorMaterials/TargetIconSpawn, but it was never saved as an export.