Blueprint Independent Rig Modules fail to keep changes to public variables inside of Modular Rigs after closing and reopening the editor

UE - ACT Character - Control Rig - Aug 11, 2026

The problem is that when adding modules in modular control rig, I can not change values for module variables - as soon as I close and reload the Unreal Editor, values snap back to default values. I ...

Unreal 5.7 Trace server not working on Rocky 8

UE - Platform - Linux - Aug 6, 2026

UnrealTraceServer built on a Rocky 8 machine yields a binary that depends on versions of glibc and glibcxx higher than the 2.28 version provided by Rocky 8.$ ldd UnrealTraceServer./UnrealTraceServer ...

Incorrect rendering result on some geometry and materials in grouped components in SKP imports

TM - Interoperability - Aug 5, 2026

Reported in SF [Link Removed] In Twinmotion 2026.1, when importing certain SKP files with grouped components, materials may render incorrectly on some grouped components and will appear with a dark ...

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. ...

FGameplayTagCountContainer::Reset() leaves explicit tag state and causes counts to accumulate

UE - Gameplay - Gameplay Tags - Aug 4, 2026

[Summary] In UE 5.7 and later, if a tag is added once to an FGameplayTagCountContainer, the container is reset, and the same tag is added once more, GetExplicitTagCount() returns 2 instead of the e ...

Color picker widget auto-closes unnecessarily

UE - Editor - Aug 3, 2026

A licensee reports that the color picket widget in Unreal Editor closes whenever a blueprint actor (map placed instance of an actor blueprint) receives a property changed event, even if the change e ...

Intermittant motion blur issues in content heavy scenes

UE - Rendering - RHI - Jul 30, 2026

When using the following RHI/Render thread/GT sync configuration:r.OneFrameThreadLag 1r.GTSyncType 1 The previous skinning bone data can be corrupted and introduce visual artifacts on everything us ...

Values passed through VertexInterpolators are incorrect in the pixel shader on Niagara mesh particles when material uses SubUV animation

UE - Rendering - Architecture - Niagara - Jul 29, 2026

Passing through the vertex interpolator, the DebugFloat3Values output appears garbled, but if you remove the VertexInterpolator the particle’s position is accurately returned. This happens with Part ...

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 ...