[UDN - 16673100] Calling FComponentVisualizer::NotifyPropertyModified() on a FInstancedStruct property loses all data inside because the PreviewActor spawns with default properties in the FInstancedStruct

UE - Editor - Workflow Systems - Jan 15, 2025

We found a problem with the component visualizer system and the PreviewActor in the Blueprint editor. If your component is using a FInstancedStruct in anyway, either directly, in a TMap, or TArray, ...

Modifying FinstancedStruct (Blueprint structs) properties inside another FInstancedStruct triggers an ensure and properties do not get saved.

UE - AI - Dec 16, 2024

There is a bug with Blueprint structs having FInstancedStruct as a property. If you modify the DefaultValues of any property of an FInstancedStruct inside the blueprint struct asset, an ensure will ...

FInstancedStruct and TInstancedStruct in DeveloperSettings only write default values to configuration ini files

UE - AI - May 6, 2025

FInstancedStructs, or its TInstancedStruct sibling, can be included in a class that inherits from UDeveloperSettings. UDeveloperSettings will persist data in a configuration file. In the case of FI ...

EditCondition tag not working for FInstancedStruct property in UDeveloperSettings

UE - Editor - Workflow Systems - May 30, 2025

When using EditCondition to control the editability of FInstancedStruct properties in a class derived from UDeveloperSettings, the condition is only partially respected. Specifically: A TArray<FIns ...

StructUtils plugin's `FInstancedStruct` in a CPP-defined struct in a `TArray` on an actor component defined in CPP and implemented in BP. Populating the instanced struct in an actor BP's class defaults breaks serialization of the class defaults.

UE - AI - May 30, 2025

Context Instanced structs are great for holding simple data with the main advantage they have is a low memory overhead unlike instanced objects. Problem The problem is in StructUtils plugin's `FIns ...

[AI] FInstancedStruct is not dupilicated properly if values are different from an Actor's defaults

UE - AI - Jan 24, 2024

A licensee reports that the values of an FInstancedStruct do not get properly duplicated if they differ from the default values of the Actor or TArray to which they belong. Possible short-term wo ...

[AI] Editor crashes when editing values of an FInstancedStruct's TArray inside of a BP

UE - AI - Jun 30, 2023

While using a custom struct that contains a TArray member variable with FInstancedStruct, you cannot edit it in the editor without a crash. Other structs and types work as expected even if they deri ...

FInstancedStruct member uproperties are not cached when "Generate Optimized Blueprint Component Data" is enabled

UE - Framework - Blueprint - Nov 18, 2025

A licensee has encountered an issue where their FInstancedStruct isn't being gathered into CachedPropertyData when "Generate Optimized Blueprint Component Data" is enabled. The changes in [Link Remo ...

Iris - Non-replicated properties of FInstancedStruct reset after replication

UE - Networking - Iris - Nov 8, 2024

This issue only occurs with Iris enabled. ...

FInstancedStruct does not serialise to JSON when used in a DataTable

UE - Editor - Workflow Systems - Aug 4, 2025

The JSON export functionality for DataTable relies on a FieldIterator to gather properties. This iterator is unable to gather the properties from the InstancedStruct. CSV export functionality works ...