Unreal Engine Issues
Unreal Engine Issues
BoxOverlapActors fails to catch an Overlaped actor with a particular scale, from a particular position
UE - Runtime - Simulation - Sep 30, 2025BoxOverlapActors fails to overlap a scaled Floor actor with a particular scale, from a particular position and extent. The setup is really specific and described in Steps to Reproduce. The required ...
Ensure triggered in FBoundsCacheElement::GetValue when adding ISM instances in Construction Script
UE - AI - Oct 8, 2025An ensure is triggered in FBoundsCacheElement::GetValue when adding instances to an InstancedStaticMeshComponent inside a Blueprint’s Construction Script. This occurs when the ISM component is navig ...
Rotated RetainerWidget does not account for rotation during hit testing
UE - AI Workflows - UI Systems - Jan 21, 2026Hit testing for widgets contained within a RetainerWidget does not correctly account for rotation applied via render transforms . While the content renders with the expected rotation, hover and clic ...
FBX Export - StaticMesh export to FBX crashes if UVElements has more channels than VertexInstanceUVs
UE - Editor - Content Pipeline - FBX - Jan 22, 2026As indicated in the repro steps, we have a StaticMesh asset that, for some reason, has a mismatch in their serialized bulk data where:MeshDescription->GetNumUVElementChannels() == 2FStaticMeshConstA ...
Cloth - Assertion failed: SimData->LODIndex != INDEX_NONE && SimData->LODIndex <= LOD when using the rewind debugger with multiple LODs cloth
UE - Runtime - Deformable - Feb 19, 2026The LOD switching when the simulation is paused could still be causing problems when the simulation is paused while the LOD indexes are going up because there is no LOD Bias mappings by default. Se ...
Geometry Collections built with "Use Root Proxies" rendering/transform positions ignore the original root node rotation and can lead to unexpected behaviors
UE - Runtime - Deformable - Nov 17, 2025Geometry Collections (GC) built with "Use Root Proxies" rendering/transform positions ignore the original root node rotation and can lead to unexpected behaviors. If the root node of the GC was rot ...
Virtual texture thumbnails appears brighter (incorrect sRGB/gamma) in content browser after asset is loaded
UE - Editor - Dec 9, 2025This is a regression, it worked correctly up to UE 5.5 but behaves incorrectly in UE 5.6 up to latest. When a regular texture with sRGB enabled is converted to a virtual texture, its thumbnail in t ...
Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)
UE - Framework - Dec 19, 2025This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...
Niagara: MeshParameterBinding property of the StaticMeshLocation module does not accept binding to parameters of type StaticMesh.
UE - Niagara - Jan 22, 2026On the details panel of the StaticMeshLocation module, when expanding the dropdown of the MeshParameterBinding property, user parameters of type StaticMesh don't show up (only those of type "Object" ...
Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine
UE - Anim - Jan 22, 2026Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine with a "Cannot replace existing object of a different class" message. The conditions to re ...