Crash when merging Skeletal Mesh with incomplete LOD streaming

UE - Runtime - Deformable - Jul 24, 2026

SummaryMerging a Skeletal Mesh whose LOD streaming has not completed crashes with an AccessViolation while the vertex copy reads the Null buffers of LODs that have not been streamed inRoot cause is ...

Tilemaps with masked materials respond to lighting at incorrect directions

UE - Gameplay - Paper2D - Nov 19, 2018

Tilemaps using lit methods of rendering are subject to strange lighting behavior. If the material for the tilemap is using a 'masked' method of rendering.  Lighting will appear at incorrect angles. ...

ShowOnlyInnerProperties does not work on a struct property in a class nested within another class as an instance

UE - Gameplay - Blueprint - Feb 19, 2019

When the ShowOnlyInnerProperties property specifier is used for a struct property, the properties contained within the struct are exposed to the Blueprints Details panel as if they were part of the ...

Crash when Undo after deleting a Material Layer of a Material Instance.

UE - Rendering - Architecture - Materials - Apr 2, 2025

In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...

Mesh painting on staticmesh doesn't always apply Colors to All LODs

UE - Editor - Open File Formats - Asset Migration - Apr 18, 2022

See the video [Link Removed] ...

Linux Crash Reporter can fail due to exceeding crash malloc space when generating the report

UE - Platform - Linux - Sep 16, 2026

On Linux a crashing process can fail to produce a crash report at all. The crash folder is created and contains CrashContext.runtime-xml and Diagnostics.txt, but the copied log file is 0 bytes, Cras ...

Exporting a spawnable through Python doesn't work

UE - Anim - Sequencer - Jan 29, 2020

CppCompileWarningSettings.NonInlinedGenCppWarningLevel messages should contain Warning\Error

UE - Core - Cpp Tools - UnrealBuildTool - Oct 8, 2025

The messages emitted when CppCompileWarningSettings.NonInlinedGenCppWarningLevel is set to Warning\Error should contain the literal so the tools pick them up and react accordingly. From the EPS c ...

Packaging for DLC with plugin multiple times causes failure due to file path length

When the DLC is being built for a project and stored in a plugin, the result is normaly until the DLC is packaged multiple times. This leads to the file path becoming more and more nested each time. ...

Crash importing morph targets with animation and opening it in animation editor

UE - Graphics Features - Mar 31, 2017

Lina encountered a crash when importing the attached FBX file with morph targets and animation, and then opening it in the animation editor. I was not able to reproduce this issue in QAGame (her re ...