BlendSpace Loop Boundary Produces Inconsistent Sync Marker Data andTriggers an AnimSequence Follower Assertion

UE - Anim - Jul 22, 2026

Summary In UE 5.7.4, when a looping BlendSpace with Match Sync Phases enabled plays as a SyncGroup Leader and crosses its loop boundary during a transition to an external AnimSequenceFollower in th ...

Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine

UE - Anim - Jan 22, 2026

Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine with a "Cannot replace existing object of a different class" message. The conditions to re ...

Deadlock in UAnimationSequencerDataModel::Evaluate where FScopeLock Lock(&EvaluationLock) blocks execution indefinitely

UE - Anim - Nov 4, 2025

When both the Sequencer Editor and an Animation Curve Editor are open for the same animation asset, the editor freezes completely upon editing the curve. Analysis indicates that the freeze is caus ...

FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern

UE - Anim - Sep 24, 2025

Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...

Mirror Data Table Asset Not Mirroring Expected Curve Names

UE - Anim - Sep 17, 2025

When mirroring the MetaHuman Face_Archetype_Skeleton it has been noticed that some curve names are not mirrored correctly (such as head_lod0_mesh_mouth_lowerLipDepress_left) while a large number of ...

Chooser Table does not support binding Gameplay Tag properties

UE - Anim - Sep 15, 2025

When using Chooser Tables, the Gameplay Tag type cannot be bound through the column header UI. Clicking a column header for a different property (ie: bool or float) correctly shows the binding popup ...

Offset Root Bone Node needs reconstruction from velocities

UE - Anim - Jul 16, 2025

The experimental Offset Root Bone node does not respect velocities, meaning that it does not work when a character is based on a moving platform. The capsule will rotate with the platform, but the r ...

RewindDebugger draws debug capsules with its base location as center

UE - Anim - Oct 31, 2024

Context UE_VLOG macros can be used to capture debug shapes into both a Visual Logger recording and a Rewind Debugger recording. Problem In the Rewind Debugger, the capsule shapes are drawn at an in ...

AnimNotifies get reproduced more times than expected.

UE - Anim - Sep 3, 2024

When setting an AnimNotify to an AnimationSequence, this AnimNotify can be triggered multiple times when only set once. This issue only happens when the mentioned AnimationSequence that contains the ...

HideBoneByName translates bone to parent which breaks skinning

UE - Anim - Jul 30, 2024

Calling HideBoneByName on a bone causes that bone (and all it's children) to be translated to the parent bone's location.  This code in UpdateRefToLocalMatricesInner is responsible: bool bNeedToHid ...