Building Geometry removes Blueprint Actors from a level

UE - Gameplay - Blueprint - Nov 28, 2022

Regression: Tested in UE5/Release-5.0, the issue does not occur so it is a regression. This issue appears to be effecting Blueprint Actors specifically, as creating a Blueprint of any other class d ...

Project Fails to Package for Windows with Steam Audio Plugin Enabled

UE - Audio - Jun 2, 2017

Projects fail to package for Windows when the Steam Audio Plugin is enabled. Errors: UATHelper: Packaging (Windows (64-bit)): xgConsole: MatTest-SteamAudio.lib(Module.SteamAudio.cpp.obj) : error LN ...

Chaos : Rigid body sleeps when very small external force is applied by AddForce

UE - Simulation - Physics - Solver - May 25, 2022

When a small external force is applied to the rigid body, the VSmooth value is reset in the ResetVSmoothFromForces function. Since this function ignores the current velocity, a very small velocity ...

Undo/Redo can cause the gizmo to desync from a leaf-selected component

UE - Editor - Workflow Systems - Oct 18, 2021

This is a regression from 4.27. This is happening because of the change to typed elements. UEditorEngine::PostUndo, when combined with the typed element changes causes the selection set to reorder ...

CitySample - Level MassCrowd - interactions with SmartObjects/ContextualAnimScene is broken in 5.5

UE - AI - Apr 9, 2025

The 5.5 version of the CitySample project, particularly the MassCrowd scene, was not properly maintained. The previously working functionality of NPCs being able to sit on a bench is now broken. CAS ...

Unable to access inherited component using Subobject Data Subsystem

UE - Gameplay - Components - Oct 3, 2023

When using the Subobject Data Subsystem (Engine\Source\Editor\SubobjectDataInterface\Public\SubobjectDataSubsystem.h), we often have to work with an instance of FSubobjectData (Engine\Source\Editor\ ...

UWorldPartitionSubsystem::IsStreamingCompleted returning the wrong query result when all cells and actors in location are in DataLayers

UE - World Creation - Worldbuilding Tools - World Partition - Jul 24, 2025

Context: Data Layers is a system within World Partition used to organize Actors both in the Editor and at runtime. It allows for the user to dynamically load and unload layers in the Editor to help ...

[CrashReport] UE4Editor_Sequencer!TBaseMulticastDelegate<void>::RemoveDelegateInstance() [delegatesignatureimpl.inl:964]

UE - Anim - Sequencer - Oct 5, 2017

This is a slightly common crash coming out of the 4.17.2 hotfix. Users have not provided any descriptions of their actions when the crash occurred. Source Context 951 /** 952 * ...

Navmesh seems to have buggy behavior when interacting with HISMCs that programmatically set mesh via SetStaticMesh.

UE - AI - Mar 6, 2020

Both versions works correctly if HISMC is pre-placed (generated in ConstructionScript). Only when generated dynamically does it fails. The Navmesh isn't being updated after SetStaticMesh and AddInst ...

[CrashReport] UE4Editor_Renderer!FUniformMeshConverter::Convert()

UE - Graphics Features - Aug 3, 2017

This is a regular crash that has occurred through 4.16 and into the 4.17 previews. The callstack is similar to [Link Removed] (invalid), although the error message is different. User Description ...