Widget animations queued before Slate creation are not carried out in UE5.8

UE - ACT Character - Sequencer - Sep 24, 2026

We are currently upgrading some of our systems from Unreal 5.6 to Unreal 5.8, and we've noticed an issue with Widget animations. In one of our commonly used actors, a Widget animation is queued in t ...

Unexpected offset when using attach tracks with scene root components

UE - ACT Character - Sequencer - Sep 15, 2026

We noticed an inconsistency when using attach tracks, depending on whether or not the parent actor has a default scene root. This creates an unintuitive behaviour for animators. It can be reproduce ...

5.8 Run Construction Script in Seqeuncer hiding control rigs

UE - ACT Character - Sequencer - Sep 15, 2026

Controls don't display in viewport if the container blueprint has "Run Construction Script in Sequencer" enabled. We've also noticed spawned control tracks temporarily disappearing from sequencer. ...

Sequencer Crash (GC Leak) in Editor

UE - ACT Character - Sequencer - Aug 31, 2026

A GC leak, similar to the one fixed by 44483919 but for Level Sequences in Level Instances rather than ones with Widgets. A Level Sequence Actor in a Level Instance points to a Level Sequence Asset ...

FCameraShakePreviewer retains world-outered UCameraShakeBase instances indefinitely, fataling CheckForWorldGCLeaks on editor map change

UE - ACT Character - Sequencer - Aug 21, 2026

FCameraShakePreviewer is an FGCObject that strongly references the UCameraShakeBase instances it previews, and creates them outered to the previewed UWorld. Nothing releases them on world teardown, ...

Crash in FMovieSceneNumericVariant::Set when loading a Level Sequence with Custom Time Warp on Android

UE - ACT Character - Sequencer - Aug 14, 2026

On Android, loading a Level Sequence fatals in the async loading thread: Assertion failed: (NewValue & ~PAYLOAD_Bits) == 0 MovieSceneNumericVariant.cpp:133 Unable to store a pointer outside of a ...

Consistent Crash using Cinematic Viewport on Linux

UE - ACT Character - Sequencer - Aug 13, 2026

We are getting multiple crashes on 5.8.1 when trying to use the cinematic viewport on Linux, the most consistent way it's been reproduced is by clicking on the blue frame number to the left of the c ...

FEvaluateActorReferenceChannels don't run on GameThread

UE - ACT Character - Sequencer - Aug 4, 2026

When playing back sequences on a character that is bound users will sometimes run into an ensure from FEvaluateActorReferenceChannels. ...

MovieSceneSequencePlayer GetEndTime() reports incorrect end time

UE - ACT Character - Sequencer - Jul 28, 2026

We've noticed an inconsistency with UMovieSceneSequencePlayer::GetEndTime(). It does not take into account DurationSubFrames. See UMovieSceneSequencePlayer::GetDuration() for comparison. Also, the c ...

MovieSceneAnimMixer: Force Root Lock suppression is editor-only, causing PIE vs cooked divergence

UE - ACT Character - Sequencer - Jul 13, 2026

The anim mixer's skeletal animation eval task suppresses an anim sequence's Force Root Lock during pose evaluation so the root-motion extraction task (FAnimNextExtractRootMotionTask) can measure and ...