SkyLight Leaking does not affect reflections when the SkyLight is static but static lighting is disallowed

UE - Graphics Features - Sep 10, 2025

Reflections do not receive SkyLight leakage contribution from a static SkyLight when static lighting is disallowed. This is caused by the function UpdateSkyIrradianceGpuBuffer checking if the SkyLig ...

Crashes occur when executing MRQ while adding UMG with RetainerBox.

UE - Editor - UI Systems - Slate - Sep 9, 2025

Create an asset containing a RetainerBox in UMG, then add the created UMG to the viewport using AddViewport. Running MRQ after this causes a crash. ...

Iris - removal of fast array item not performed on client when server array contains a non-replicated item

UE - Networking - Iris - Sep 8, 2025

It is possible to add items to a replicated fast array that are not intended to be replicated to the clients. For example, FGameplayAbilitySpecContainer has a custom ShouldWriteFastArrayItem impleme ...

Undoing keyframe addition in Sequencer unselects actors in the Outliner

UE - Anim - Sequencer - Sep 8, 2025

When a keyframe is added to a track in the Sequencer, undoing the operation correctly removes the keyframe, but it also unselects the actor. This becomes especially inconvenient when multiple actors ...

Mover character stuck continuously correcting movement after having a skeletal mesh as movement base

UE - Gameplay - Player Movement - Mover - Sep 8, 2025

Once a mover character has had a skeletal mesh set as its movement base, it appears to get stuck in a desynced state after moving to a static movement base. It is only when the character's movement ...

[AI] Failed check in UMassSpawnerSubsystem::DestroyEntities due to EntityManager still procesing

UE - AI - Mass - Sep 7, 2025

It crashed when unspawning an AI which will destroy its entity. Inside DestroyEntities "IsProcessing" is true, but when it breaks into the debugger, "ProcessingScopeCount" is 0 (so IsProcessing shou ...

ensure(PinHelpers::UnresolvedPins.Num() == 0); fails after undoing in the editor

UE - Framework - Blueprint Editor - Sep 6, 2025

The underlying cause is some edge case involving a math expression node, which does some perhaps naive things with a contained graph. ...

Crash when changing r.MaterialQualityLevel when FastGeo plugin enabled in cooked build

UE - World Creation - Worldbuilding Tools - Sep 5, 2025

The engine crashes when the r.MaterialQualityLevel is changed in a cooked game that uses the FastGeo Streaming Plugin. The crash doesn't repro with the same steps in Editor, just in a cooked build. ...

Crash when opening a texture or editing its properties after stopping a preview in the material editor

UE - Rendering Architecture - Materials - Sep 5, 2025

When a texture asset has certain properties edited, its PostEditChangeProperty() method calls to UTexture::NotifyMaterials(), which triggers a recompilation of materials that reference it in their m ...

'Malformed sequence hierarchy' ensure hit after modifying sub-sequence tracks

UE - Anim - Sequencer - Sep 5, 2025

It's possible for there to be multiple instances of the same sequence in the evaluation states cache if the same sequence is used in multiple sub-sections. Caches are never removed from the evaluat ...