Custom Debug Camera Is Not Respected If Set Anywhere Other Than Code

UE - Gameplay - Gameplay Cameras - Sep 11, 2026

The correct debug camera is no longer used if the class is set in a config file or within the Editor. When the debug camera is toggled on, the default will be used instead. If the class is set in co ...

Scrubbing the timeline in Sequencer can hang the editor when operating on constrained actors with complex control rigs

UE - ACT Character - Anim in Engine - Sep 11, 2026

The issue is caused by UAnimDetailsProxyManager::ForceUpdateProxyValue triggering evaluation of constraints that are attached to control rigs. When scrubbing, requests to ForceUpdateProxyValue are ...

Race condition in GetFunctionSig_Write() and other function signatures

UE - Rendering - Architecture - Niagara - Sep 11, 2026

A race condition exists in GetFunctionSig_Write() and other places where FNiagaraFunctionSignature  is lazily initialized because multiple worker threads can progress past if (!Sig.IsValid()) and st ...

Motion blur artifacting in MetaHuman Crowd demo

UE - Rendering - Features - Sep 10, 2026

This issue was reported by a licensee and we also hit it during dev work on the crowds demo. It seems that this may be a general issue with motion vectors and teleporting actors as there are variou ...

LevelInstance\PackedLevelActor: Problem with non-uniform negative scale.

UE - Engine Scaling - Streaming - Sep 10, 2026

A licensee is reporting transform issues related to using non-uniform negative scale on LevelInstances and PackedLevelActors. ...

TMap where key is an FString: initializer list will accept bad MakeTuple

UE - Core - Systems - Sep 2, 2026

POST 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 ...

Crash when a floor mesh is removed while a Vehicle has SimulatePhysics disabled

UE - Runtime - Character - Sep 1, 2026

When SimulatePhysics is disabled, the constraint update is skipped, so a reference to an invalid (already-removed) particle is left behind. As a workaround, the approach suggested by the licensee — ...

Level Sequence spending long time validating assets

UE - ACT Character - Control Rig - Aug 31, 2026

Hi After migrating our animation project from 5.7 -> 5.8 we notice that some level seqeunces take much longer to save (during validation stage). This issue only exhibits when using control rigs in ...

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 ...