Unreal Engine Issues
Unreal Engine Issues
Skeletal mesh reimport via legacy import creates duplicate Mesh sockets
UE - Editor - Content Pipeline - Import and Export - Feb 25, 2026Reimporting a Skeletal Mesh via legacy import duplicates mesh sockets. The issue does not reproduce when using the Interchange pipeline. ...
Cook Non-Determinism in USplineComponent
UE - Editor - Feb 25, 20261. Non-Deterministic LastAuthority Serialization LastAuthority is assigned in USplineComponent::Serialize. Its value depends on the order in which the object and its archetype are serialized, leadi ...
Crash caused by a race condition in Nanite::DispatchBasePass()
UE - Rendering - Graphics Features - Nanite - Feb 25, 2026Nanite::BuildShadingCommands() launches two asynchronous tasks: ShadingCommands.SetupTask ShadingCommands.BuildCommandsTask BuildCommandsTask is responsible for modifying ShadingCommands.Commands ...
Cluster Group Index Causes Incorrect Break Events in Geometry Collections
UE - Runtime - Deformable - Feb 25, 2026More details in this [Link Removed] ...
Visual discrepancy between lighting in Cloud Presenter and editor viewport
TM - Rendering - Feb 24, 2026Reported in SF [Link Removed] In this user’s scene, the lighting in the Cloud Presenter does not match the lighting in the editor viewport. The Cloud scene is notably darker than the editor. The s ...
Motion Matching FPS instability causes jittering when using the root offset node
UE - Characters - Animation - Feb 23, 2026Offset root node is affected by frame rate and produces jitter in it's motion across various settings and styles. ...
Occlusion Queries for Static Meshes with ERuntimeVirtualTextureMainPassType::Exclusive
UE - Rendering - Architecture - Feb 20, 2026Static Meshes that draw into RVTs and have "Draw In Main Pass" is set to "From Virtual Texture" (ERuntimeVirtualTextureMainPassType::Exclusive) will still draw in Occlusion Queries. This can be tr ...
Unstable automation tests in "Standard Tests" list.
UE - Rendering - Architecture - Feb 20, 2026The two following automation tests found in the "Standard Tests" list hit exceptions & cause the editor to crash:System->Physics->Interface->BodyInstanceShaders->ShaderPreprocessor->BuiltInMacros ...
anim notify states are triggered when updating thumbnails
UE - Runtime - Animation - Feb 19, 2026The issue is that FAnimationSequenceThumbnailScene::SetAnimation calls referesh bone transforms which will trigger notify states present at the midpoint of the animation (as the thumbnail code sets ...
Precaching global shaders with r.PSOPrecache.GlobalShaders = 2 crashes on startup
UE - Rendering - Architecture - RHI - Feb 19, 2026A licensee has reported that they are trying to run a cooked project with r.PSOPrecache.GlobalShaders=2 and running into a crash. They believe the problem is in PrecacheComputePipelineStatesForGlob ...