Potential issue with components being created inside of components, with the outer component added to a BP

UE - Gameplay - Components - Nov 6, 2015

If a static mesh component is added to a scene component class and the scene component is added to an actor - the static mesh that is assigned in the blueprint will not show up in the blueprint edit ...

UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation

UE - Editor - Open File Formats - May 1, 2025

UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation. The K2Result is not used later in the function, and this ...

Code delegates duplicate function calls when owning actor is duplicated in the editor

UE - Foundation - Core - Jan 15, 2016

If an actor that contains a delegate bound in code is duplicated after being placed in the level, the delegate for the duplicate will also trigger the delegate for the original as well. ...

Python function unreal.AssetRegistry.get_assets_by_class is broken

UE - Core - Systems - Nov 21, 2022

Repro Rate: 3/3 This issue was reproduced in //UE5/Release-5.1 at CL 23058290. This is confirmed to be a regression since the errors do not occur on the previous version and is regression tested o ...

Skeletal mesh LODs never stream up under SSAM: FSkeletalMeshSceneProxy caches ForceStreamedLOD and is never re-gathered

UE - Engine Scaling - Streaming - Jul 29, 2026

UE 5.8, cooked build, SSAM enabled (s.StreamableAssets.UseSimpleStreamableAssetManager=1, required by FastGeo). Symptom: characters spawn at a crude LOD and can never stream up for the lifetime of ...

Crash when travelling during ability activation when URL contains "#"

UE - Framework - Jul 18, 2025

This issue is related to [Link Removed] Closed , where the "?listen" option sent on the URL to clients could cause issues wi ...

World Initialization is performed on Transition World if the client's process is halted at a certain point

UE - Networking - Apr 12, 2016

A user reported an issue where, if a client hitches during world transition, the client will continue referring to the transition world instead of the newly created one. This will result in the clie ...

UBT crashes when doing an incremental build

UE - Foundation - Cpp Tools - UnrealBuildTool - Aug 9, 2017

There is a consistent crash when incrementally compiling headers containing generated code. The code for launching UHT accesses a property which is null when compiling with the UBT makefile. ...

.ini files for packaged games have their settings wiped clean every time the game is run.

The settings .ini files for games packaged for windows appear to be getting overwritten with blank files whenever the game is run. Even if settings are added to the .ini files manually, the files be ...