Creating Widget at run time with an exposed variable causes Engine crash with Assertion

Tools - May 8, 2020

If you are using the default values of the In Size the project will run fine, but changing the values will make the engine crash. This was reported and tested in 4.25 (CL-13144385) and reproduced i ...

When using Subversion (SVN) and Lock's comment is Japanese outside SourceControl, parsing of xml fails and Status may become NotControlled.

UE - Foundation - Core - Jun 28, 2019

If user lock assets with Japanese comments outside source control, XML acquired in svn status may contain Japanese strings, and XML parsing may fail and become NotControlled. This issue does not oc ...

Editor crashes when replacing Packed Level Actor assets during asset deletion process

UE - Engine Scaling - Streaming - Level Instances - Feb 6, 2024

Maximum number of State Machine connections?

OLD - Anim - Mar 16, 2015

Adding more than 8 connections to or from a state in the state machine results in unpredictable behavior, like causing an animation to fail. (See image.) Was able to reproduce with user's test file ...

Interchange GLTF importer truncates skeletal mesh bone influences to 4 per vertex

UE - Editor - Open File Formats - Aug 21, 2026

cf https://forums.unrealengine.com/t/interchange-gltf-importer-truncates-skeletal-mesh-bone-influences-to-4-per-vertex/2745391/2 Original message The UE5 Interchange GLTF importer appears to trunc ...

[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 ...

[CrashReport] UE4Editor_CoreUObject!FScriptArrayHelper::EmptyAndAddUninitializedValues() [unrealtype.h:2703]

UE - Gameplay - Blueprint Compiler - Aug 15, 2017

This is a trending crash coming out of the 4.17.0 release. Based on user descriptions, this crash occurs on Play or Compile for affected users. User DescriptionsAgain crashing when I hit playIF I C ...

[UDN - 00707230] DetailLayoutHelpers ensure when using VisibleAnywhere Instanced properties

UE - Editor - Verse Class Editor - Jan 11, 2024

From UDN Description Hello, there's an ensure that's firing in `DetailLayoutHelpers.cpp#137`: [Start code block] ensure(PropertyNodeMap.ParentProperty == CurObjectNode); [End code block]when ...

FStateTreeRunParallelStateTreeTask and TStateTreePropertyRef

UE - AI - StateTree - Dec 2, 2025

When using a state tree that has a StateTreePropertyRef as a parameter in parallel any references will fail to resolve using the GetPropertyRef node. ...

[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. ...