BP hierarchy change triggers incorrect map actor load warning: AttachTo: '{0}' is not static {1}, cannot attach '{2}' which is static to it.

UE - Framework - Blueprint - Apr 11, 2024

When a blueprint's component hierarchy is changed by changing a child component's mobility value to Static while deleting its parent component which has Movable mobility, levels saved with an outdat ...

Crash when Previewing specific LODs within Static Mesh Editor at certain Screen Resolutions

Tools - Oct 27, 2016

A crash occurs when attempting to preview specific LODs when the monitor resolution forces the menu to be expanded when selecting an LOD. This Jira was created from CrashReports submitted by the pu ...

Niagara color picker user parameter preview no longer updates until confirmation

UE - Rendering - Architecture - Niagara - Apr 18, 2025

Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...

Crash on iOS9 when using Apple's CFNetwork library

UE - Platform - Mobile - Dec 6, 2016

Many clients have hit a crash due to an Apple library using operator delete on a memory block that was not allocated with operator new. This happens with the following callstack on iOS9 in UE4.13 o ...

Camera Component - Regression in Unreal 5.7+

UE - QA - Support - Oct 4, 2026

POST BODY:Summary Hey there - I’ve been sticking with Unreal Engine 5.6 for cinematics because of a regression that's been made to CineCameraActors (specifically the CameraComponent nested inside of ...

Behavior Tree (BT) services added to root nodes call the initial tick twice

UE - AI - Nov 20, 2024

Behavior Tree (BT) services added to root nodes call the initial tick twice A BT Service with the setting "Call Tick on Search Start" enabled will execute the initial tick twice when added to the ro ...

BuildPatchTool crashes on Mac and Linux when building android or ios with multiple chunks

Portal - Feb 18, 2020

"It seems that deallocation of TLazySingleton<FInternationalization> causes unhandled exception. If DISABLE_LAZY_SINGLETON_DESTRUCTION=1 is provided - the build completes successfully" ...

Editor crashes due to a material that contains MPCs migrated from another project

UE - Rendering - Architecture - Materials - Apr 29, 2024

[2024.04.29-16.49.46:563][970]LogUObjectGlobals: Warning: LoadPackage can't find package /BEURRE_040824_041224/NewMaterialParameterCollection. [2024.04.29-16.49.46:563][970]LogUObjectGlobals: Warning ...

Search field in 'Quickly Add to Project' fails with Chinese Pinyin input unless manually focused

UE - AI Workflows - UI Systems - Localization - May 28, 2025

A licensee reported that under the Chinese language setting in UE5, using the “Quickly Add to Project” button results in incorrect or ignored input when entering text via Pinyin IME. If the user sta ...

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering

UE - Runtime - Deformable - May 10, 2025

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering. Once the Remove-On-Break Cluster Crumbling effect is activated, there is a small delay between the disappearance of th ...