Unreal Engine Issues
Unreal Engine Issues
Sequencer Crash (GC Leak) in Editor
UE - ACT Character - Sequencer - Aug 31, 2026A 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 ...
[Mutable] Morph Targets can be disabled in packaged builds when Mesh Streaming is enabled
UE - Runtime - Mutable - Aug 28, 2026When a Mutable mesh instance is created while the actor spawns at a distance, only the low LODs are generated, and the mesh is created with no Morph Targets registered. Later, when the camera approa ...
Editor crash when an unsupported material domain or blend mode is selected when previewing a Nanite mesh in the material editor
UE - Rendering - Features - Nanite - Aug 27, 2026Fix in UE6: 56133257 This Jira is for 5.8.3 tracking ...
Cannot get Texture Size property from Texture Collections
UE - Rendering - Architecture - Materials - Aug 26, 2026The following error is shown when attempting to use the Texture Size of a Texture Collection texture object: Texture size only available for Texture2D, TextureVirtual, Texture2DArray, VolumeTexture ...
MRG - Cinematic Assembly Tokens From Metadata Return Empty When Rendering
UE - CAPT - Color Pipeline and Rendering - MRQ - Aug 25, 2026Metadata defined on a Cinematic Assembly isn’t accessible as naming tokens when rendering with Movie Render Graph. Global naming tokens defined outside of a Cinematic Assembly does work but context ...
MID TextureCollections don't work with Post Process Overlays
UE - Rendering - RHI - Aug 24, 2026TextureCollectionParameters in a material assigned to a Post Process Overlay are not overridden by a MID because CopyInterpParameters in Engine\Source\Runtime\Engine\Private\Materials\MaterialInsta ...
Unable to kill UnrealBuildTool, UBT no longer propegates sigterm
UE - Core - Cpp Tools - UnrealBuildTool - Aug 24, 2026When UBT is launched through one of the standard wrapper scripts, Ctrl-C no longer cancels the build. The `dotnet UnrealBuildTool.dll` process and its compile actions keep running to completion in t ...
FCameraShakePreviewer retains world-outered UCameraShakeBase instances indefinitely, fataling CheckForWorldGCLeaks on editor map change
UE - ACT Character - Sequencer - Aug 21, 2026FCameraShakePreviewer is an FGCObject that strongly references the UCameraShakeBase instances it previews, and creates them outered to the previewed UWorld. Nothing releases them on world teardown, ...
Chaos Mover crash in standalone editor client
UE - Runtime - Character - Aug 18, 2026When using the Chaos Mover with resimulation enabled, standalone editor processes running as a client will crash around 80% of the time upon startup. ...
Consistent Crash using Cinematic Viewport on Linux
UE - ACT Character - Sequencer - Aug 13, 2026We are getting multiple crashes on 5.8.1 when trying to use the cinematic viewport on Linux, the most consistent way it's been reproduced is by clicking on the blue frame number to the left of the c ...