Unreal Engine Issues
Unreal Engine Issues
Attached actors have AttachmentReplication marked as dirty every net update
UE - Networking - Feb 11, 2026In AActor::GatherCurrentMovement, bWasAttachmentModified will be set to true if the actor’s root component has an AttachParent, even if none of the values in the AttachmentReplication struct have ch ...
Division by zero causing NaN/Inf on USkeletalMeshComponent::UpdateRigidBodyScaling() when setting scale to zero and back
UE - Anim - Rigging - Feb 11, 2026Up to UE 5.5, skeletal mesh physics did not get updated when the component's scale changed. This was improved on January 2025 with CL 39190335, which addressed [Link Removed] ...
Enum Compare Condition causes crash when resetting default value of right field in State Tree's Enter Conditions
UE - AI - StateTree - Feb 11, 2026In FStateTreeCompareEnumCondition::GetDescription, the Left.Enum value is mistakingly used when setting the RightValue. This causes crashes when resetting the default value of the Right field in an ...
StaticMesh reimport not preserving support for physical material masks
UE - Simulation - Core - Feb 10, 2026Client has a workflow issue with the reimport pipeline: UStaticMesh::bSupportPhysicalMaterialMasks should be copied over to UBodySetup::bSupportUVsAndFaceRemap before it takes effect for raycasts, ...
FDetailGroup::AddGroup does not correctly apply the default expansion state for DetailGroups
UE - Editor - Workflow Systems - Feb 10, 2026There is a bug affecting DetailGroups in the engine. When adding child DetailGroups to a parent DetailGroup, the expansion state does not behave as expected and ignores the flags intended to control ...
Directly opening a modified map asset of a streaming sublevel does not always force it to be reloaded (inconsistent with other map open behaviors)
UE - World Creation - Worldbuilding Tools - Feb 10, 2026When the level currently being edited has unsaved changes and the user opens a new one, the Editor asks if the changes should be saved. If the user answers negatively, the level asset is reverted to ...
Horde - Endpoint and parameter name mismatches between some requests sent by HordeHttpclient and the corresponding handler functions on server controllers.
UE - Foundation - Horde - Feb 10, 2026Class HordeHttpClient has some Async Task methods to make HTTP requests to the Horde Server. In particular, method GetProjectsAsync() sends a request to endpoint "api/v1/projects" with query paramet ...
Using VSM and Distance Field Shadows on the same scene results in missing shadows
UE - Rendering - Graphics Features - Shadows - Feb 9, 2026Nanite geometry does not cast Distance Field Shadows outside of the clipmap range for Virtual Shadow Maps. Non-Nanite geometry does cast these shadows. ...
Client disconnected due to MissingLevelPackage in editor with Iris and server streaming enabled
UE - World Creation - Worldbuilding Tools - World Partition - Feb 9, 2026When connecting to the server, if the client activates some local cells while the connection is still pending, ULevelStreaming::IsConcernedByNetVisibilityTransactionAck will return false. In this ca ...
Missing logging or error when applying an anim instance to a skeleton that the anim instance doesn't match.
UE - Anim - Runtime - Feb 9, 2026Currently, we detect whether an anim instance is supported by the skeletal mesh and, if it isn't, unreference the instance, but we don't error or warn the user that this happened. This leads to conf ...