Unreal Engine Issues
Unreal Engine Issues
Custom Primitive Data is not affected in the skeletal mesh on BP instances in the editor
UE - Rendering - Architecture - Jan 22, 2026Editing Custom Primitive Data values in the details panel of a placed BP actor with a Skeletal Mesh component does not reflect in the Editor viewport. ...
Missing Triangles on scaled MetaHuman assets with Nanite enabled
UE - Rendering - Features - Nanite - Feb 19, 2025Additional information: only happens when all three conditions are true: the camera is very close to the character, the MH is Nanite, and a scaled mocap animation is appliedmaterial is opaque, shows ...
Sequencer.AllowPausedClock makes Audio/Platform-clock sequences evaluate at a negative time after any earlier game pause
UE - ACT Character - Sequencer - Oct 17, 20265.8 added Sequencer.AllowPausedClock (on by default) in FMovieSceneTimeController_ExternalClock::OnRequestCurrentTime (MovieSceneTimeController.cpp): PausedTime = Context.World()>RealTimeSeconds - ...
Chaos: geometry collection with One Way Interaction never breaks from its own collisions
UE - Runtime - Simulation - Aug 21, 2026A geometry collection with One Way Interaction Level set to 0 never breaks from its own collisions. It falls, lands, and stays intact no matter what it hits. Set the level to -1 (feature off) and ch ...
[Mobile/Forward Rendering] PlanarReflection does not work when the reflection plane faces certain directions
UE - Platform - Mobile - Systems - Sep 24, 2025Note: This repros on 4.27 and all 5.x versions. When using the mobile renderer and/or forward shading, Planar Reflection will simply not work if the reflection plane normal has components that add ...
Having a block in layout before switching to overlay strategy affects the overlay output.
UE - Runtime - Mutable - Mar 5, 2026Issue: If "Resizable" Layout Strategy contains a block, it will influence the "Overlay" Layout Strategy. Expected behavior: When using "Overlay" Layout Strategy, it should disregard whatever the "R ...
Nanite Landscape Visibility Layer Crash
UE - Graphics Tools - Terrain - Landscape - Jun 10, 2026Upon saving the level after creating the landscape and painting visibility, the editor crashes. When you restart the editor and load the level, you are greeted with a warning in the upper right corn ...
[CrashReport][Crash] Engine!FSceneViewport::UpdateViewportRHI() [SceneViewport.cpp]
UE - Rendering - RHI - May 29, 2026#200 crash out of 2101 in UE 5.8 on Windows#34 crash for UE - Rendering - Architecture in UE 5.8 on Windows#20 crash for UE - Rendering - Architecture - RHI in UE 5.8 on WindowsAssertion failed: IsI ...
FMassMoveTargetFragment::CreateNewAction does not update PreviousAction, breaking the start-of-path avoidance fade and related behavior for MassEntity crowds
UE - Runtime - Character - Jul 28, 2026In MassEntity-based crowds, when an agent transitions from Stand to Move and begins walking, the Avoidance trait parameters StartOfPathDuration and StartOfPathAvoidanceScale, which are meant to temp ...
Landscape has a seam when scale is set to a decimal
UE - Graphics Tools - Terrain - Landscape - Jan 13, 2023Regression: Tested in UE5/Release-5.0 at CL 20979098, this issue does occur so it is not a regression. This issue occurs if the scale set for the landscape has a decimal value that is not 0.5. Sett ...