Virtual Bone caused nanite skinned mesh crash

UE - Rendering - Features - Nanite - May 31, 2025

When a Nanite skeletal mesh has a virtual bone the engine can crash when changing LODs ...

Performance hitch from RemoveGeometryCache flushing the render thread

zComponent - Archive - Jun 12, 2025

FGeometryCacheStreamingManager::RemoveGeometryCache calls FlushRenderingCommands which shows up as a hitch when profiling. [Link Removed] Ideally the flush added in CL#23782411 to fix a rare deadl ...

Significant hitch occurs when invoking ApplySettings on a UGameUserSettings object

UE - Rendering - Features - Jun 18, 2025

Calling the ApplySettings method on a UGameUserSettings object results in a noticeable hitch, with severity proportional to the number of primitive components present in the scene. This hitch stems ...

When exporting static meshes with bExportSourceMesh enabled, there is a problem where all UVs are fragmented.

zComponent - Archive - Sep 22, 2025

From customer: "In the StaticMesh Export option, when bExportSourceMesh is set to True, exporting StaticMesh Assets and importing them into DDC tools such as 3dsMax or Maya results in the UVs being ...

Iris - Initially dormant actors not replicated if dormancy is not enabled

UE - Framework - Networking - Feb 16, 2026

With dormancy disabled, it seems that actors marked as dormant are not registered as expected with Iris. Even if the actor is woken up or flushed before making changes to its properties, the client ...

If 'Enable Physics Interaction' is disabled, the player can still interact with physics objects

UE - Gameplay - Oct 22, 2015

If 'Enable Physics Interaction' is disabled, the player can still interact with physics objects User Description: I have a Bus Vehicle with custom physics (skeletal mesh). So I can walk through th ...

Game sounds only play during first PIE editor session for Linux project

UE - Platform - Linux - May 11, 2015

Games sounds will play as appropriate during first PIE session but subsequent PIE sessions have no sound until editor is closed / reopened. ...

Confusion over what assets are saved in Persona with the Toolbar button

OLD - Anim - Jun 24, 2015

Some users appear confused as to why the skeleton is not saved when they add sockets while in Animation Editing Mode. Unsure what an elegant solution would be at this time. ...

The Default Value for a Timespan variable resets whenever its Blueprint is compiled

UE - Gameplay - Blueprint - Nov 30, 2014

The Default Value for a Timespan variable resets to 00:00:00.000 whenever its Blueprint is compiled. ...

Skeletal mesh jerks backwards when moving capsule component back to skeletal mesh with physics enabled

UE - Simulation - Physics - Jul 27, 2015

If a skeletal mesh utilizing a capsule component has physics enabled to ragdoll, when the capsule is moved back to the mesh the mesh will jerk backwards towards the capsule briefly. ...