Unreal Engine Issues
Unreal Engine Issues
Morph target is not applied on the first frame in Level Sequence
UE - ACT Character - Control Rig - Dec 4, 2025When a skeletal mesh with morph targets spawns in the sequence, the morph is not reflected in the first frame. In the ProcessStage_SkinCache call of SkeletalMesh, MorphVertexBuffer->SectionIds is ...
[CrashReport] UE4Editor_Sequencer!FSequencer::NotifyMovieSceneDataChanged()
UE - Anim - Sequencer - Jul 24, 2017This is a common crash affecting users in 4.16 and into the 4.17 Preview. User Descriptionscopying-pasting curves in Sequencer Source Context 979 void FSequencer::NotifyMovieSceneDataCha ...
ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision
UE - Runtime - Simulation - Jan 27, 2025ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision. The licensee reports one of their users reported this issue and they were able to reproduce a fe ...
[CrashReport] UE4Editor_Renderer!FGlobalShader::SetParameters<FRHIPixelShader * __ptr64,FRHICommandList>() [globalshader.h:134]
UE - Graphics Features - Jun 29, 2016This JIRA was created from crash reports submitted by users due to it being one of the top crashes occurring in 4.12.4 This might be a regression because the crash has only just started in 4.12.4. ...
TMap where key is an FString: initializer list will accept bad MakeTuple
UE - Core - Systems - Sep 2, 2026POST LINK: https://forums.unrealengine.com/t/tmap-where-key-is-an-fstring-initializer-list-will-accept-bad-maketuple/2747443 POST BODY:Summary A TMap where the key is an FString can be created lik ...
Sequencer causes 3DWidget on BP vectors to snap to Actor when active
zComponent - Archive - Nov 15, 2025When we have Vectors in BP with Show 3D Widget enabled, the Transform Widget would always snap back to the Actor after we move the 3D Widget in-world. [Link Removed] Removing the _DaySequenceActor ...
GAS: Mixed replication mode and error in MinimalReplicationTags code
UE - Gameplay - Gameplay Ability System - Apr 6, 2022We're on 4.25.4. We recently turned on mixed mode replication for GAS, which seems to work fine and reduce bandwidth as expected. However one of our unit tests started failing with this error messag ...
[CrashReport] UE4Editor_UnrealEd!UFbxSceneImportFactory::ImportOneSkeletalMesh() [fbxsceneimportfactory.cpp:2017]
Tools - Nov 10, 2017This is a trending crash coming out of the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Source Context 2014 USkeletalMesh *ImportedSkelMes ...
Composite font uses a sub-font, even when the sub-font doesn't support the character
Tools - Apr 7, 2016I have a fix for this shelved in CL# 2937344, so it would be good to get it into 4.12 once the user verifies the fix. ...
Crash: Direct3DDevice->CreateBuffer failed at D3D11VertexBuffer.cpp with error E_INVALIDARG
UE - Graphics Features - Jul 6, 2017This is a common crash affecting users since at least the 4.14 release. It was previously associated with [Link Removed], however that has been marked as fixed. Source Context 221 void Veri ...