Ensure breaking a link in anim blueprint Event Graph and then undoing

UE - Gameplay - Blueprint Editor - Jul 18, 2016

Ensure occurs when the user breaks a link in the animation blueprint's Event Graph and then undo's the action. I wasn't able to reproduce it in a class blueprint. ...

[CrashReport] Crash on Mac during cook - UEditorEngine::UpdateAutoLoadProject()

UE - Platform - Apple - Jun 6, 2017

This is a top crash on Mac. This crash has only occurred on the 4.16.1 release (there are no records of it in 4.16.0). Repro steps are currently unknown, but the crash occurs in Commandlet mode and ...

Control Rig settings are not retained between editor sessions or carried into deployed game

UE - Anim - Rigging - Control Rig - Jun 10, 2020

Control Rig settings are not retained between editor sessions or carried into deployed game ...

[CrashReport] Mac crash - TArray<FDeferredMacEvent, FDefaultAllocator>::ResizeGrow

UE - Platform - Apple - Sep 14, 2017

This is a somewhat common crash on Mac that has affected users since 4.16. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log [2017.09.08-05.17. ...

Wrong WPO motion vectors due to Periodic World Space node

UE - Rendering - Graphics Features - May 13, 2026

We've noticed smearing in grass due to wrong motion vectors. This appears to be caused by lack of previous frame support in the periodic world space node. This is how we fixed it: In MaterialTempl ...

Compiling a blueprint with SetCollisionResponseToChannel Causes Crash

UE - Gameplay - Dec 5, 2016

When using a blueprint with a destructible component, you can call the SetCollisionResponseToChannel node of that component in the construction script. As a result the engine will crash when attempt ...

Crash when destroying a pawn on the client

UE - Networking - Jul 6, 2015

Crash when destroying a pawn on the client. Reproduced in 4.8.1 and Main (//depot/UE4/Promotable-CL-2610743). This is a regression: the crash does not occur in 4.7.6 Crash Report: [Link Removed] ...

Unexpected behavior when Actor Parenting in the World Outliner of a WP map

UE - World Creation - Worldbuilding Tools - World Partition - Nov 23, 2021

Licensee reports the following in the UDN: There seems to be some other erratic behavior when using parenting in world outliner (i.e. drag and drop one actor on another one in world outliner).Since ...

Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)

UE - Framework - Dec 19, 2025

This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...

Light baking of a ton of static meshes causes Swarm to crash.

UE - Foundation - Cpp Tools - Mar 25, 2019

Light baking of a ton of static meshes causes Swarm to crash due to "Index was our of range". I confirmed that it can be reproduced with the sample project they sent us/ The error log I got is... ...