StaticMesh reimport not preserving support for physical material masks

UE - Simulation - Physics - Feb 10, 2026

Client has a workflow issue with the reimport pipeline: UStaticMesh::bSupportPhysicalMaterialMasks should be copied over to UBodySetup::bSupportUVsAndFaceRemap before it takes effect for raycasts, ...

Client disconnected due to MissingLevelPackage in editor with Iris and server streaming enabled

UE - World Creation - Worldbuilding Tools - Feb 9, 2026

When connecting to the server, if the client activates some local cells while the connection is still pending, ULevelStreaming::IsConcernedByNetVisibilityTransactionAck will return false. In this ca ...

Missing logging or error when applying an anim instance to a skeleton that the anim instance doesn't match.

UE - Anim - Runtime - Feb 9, 2026

Currently, we detect whether an anim instance is supported by the skeletal mesh and, if it isn't, unreference the instance, but we don't error or warn the user that this happened. This leads to conf ...

[AI] Navmesh tiles are fully removed when a tile containing an automatic navlink is regenerated using Dynamic Modifiers Only generation

UE - AI - Navigation - Feb 9, 2026

An unusual interaction has been found when using automatic navlink generation combined with Dynamic Modifiers Only navmesh generation. When an nav area is modified in a tile that contains an automat ...

Using PCG, StaticMeshComponentPropertyOverride only takes effect when the flag ExecuteOnTheGPU is off.

UE - World Creation - Procedural Tools - Feb 9, 2026

StaticMeshComponentPropertyOverride only takes effect when the flag ExecuteOnTheGPU is off. All error checking for StaticMeshComponentPropertyOverride turns off when the flag ExecuteOnTheGPU is off ...

MRG - Additional Post Process Render have a black alpha channel

UE - Virtual Production - Tools - MRQ - Feb 7, 2026

Additional Post Process renders always have a black alpha channel ...

Chaos Cloth - Multiple issues with convex colliders

UE - Simulation - Visual - Feb 6, 2026

Issue 1: Convex Collision Transformation Missing for External Collision Sources Issue 2: Convex CCD Stability Issues due to Plane Intersection Semantics See attached URL for more details. ...

Object Columns using soft asset references will return null results

UE - Anim - Gameplay - Feb 6, 2026

We have encounter an issue in the Chooser when we setup output object column for soft reference object ptr (an optional montage object). It is working correctly when the montage is loaded. But befor ...

Animation compression deadlock

UE - Anim - Runtime - Anim Blueprints - Feb 5, 2026

The deadlock occurs when attempting to cancel compression during animation sequence destruction. The compression thread ends up deadlocking with the game thread, which is the one requesting the canc ...

Drag and drop does not work from a window created with PySide

UE - Editor - Workflow Systems - Feb 5, 2026

The cursor position is no longer updated during drag and drop, so drag-over events cannot respond correctly. Commenting out the following code in WindowsCursor.cpp works as a workaround ( the behavi ...