Unreal Engine Issues

UnrealGameSync update check not working if Horde is set as an update source

NaN Present on IOS after UE5.6 Because of Removal of MobileSpecularGGX

In UE5.6 MobileSpecularGGX was removed and now mobile devices also run D_GGX. The problem is that there are still cases where very bright values are produced (image 1) and thus NaNs appear in the Bl ...

Iris - actors spawned/loaded before a connection exists will not use delta compression

FDeltaCompressionBaselineManager::CreateBaseline will return early if the object has an invalid ObjectInfoIndex, which is allocated in FDeltaCompressionBaselineManager::UpdateScope (by calling FDelt ...

FBlackboardKeySelector filters aren't applied when recompiling blueprint if a behavior tree asset containing the blueprint added as a service is closed, or if the blueprint is reparented.

Context In Behavior Trees, BT Services can be added to nodes. Those services can have configurable FBlackboardKeySelectors. BlackboardKeys are variables on a blackboard that the behavior tree can r ...

Post Process Animation Blueprint Crash When Using Blend Node

When using a Blend node inside a Post Process Animation Blueprint, the editor crashes while rendering thumbnails. The crash occurs because USkeletonThumbnailRenderer attempts to draw a thumbnail wit ...

FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern

Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...

Xcode 26/16.4 Metal Toolchain generates metallib's that are not compatible with iOS 16

Below is the error output from FirstPerson template as a C++ project: {+}../../../FirstPerson58CPP/Content/firstperson58cpp_sf_metal_es3_1_ios-metal_es3_1_ios.0.metallib, 5881486 bytes!2025-09-23 1 ...

Cook Warning "Saving FText which has been initialized from FString" when a user-defined BP structure contains a native C++ struct with an FText

Consider a C++ struct containing an FText. Now consider a used-defined BP structure containing that C++ struct. When cooking an asset that references such a user-defined BP structure, the following ...

New folder shortcut (Ctrl+Shift+N) does not work in multi-Content Browser layouts until a folder is manually focused

In multi–Content Browser layouts, the New Folder shortcut (by default Ctrl+Shift+N) does not work immediately after switching to another Content Browser tab. It appears that the editor does not auto ...

Mutable constant texture variable with ClipUV mask only works with new experimental dynamic variable is connected as well

We are attempting to use Mutable in 5.6.1 and have encountered an issue which we are not sure how to resolve. The issue occurs when using the ClipWithUVMask node. In short we have a customizable o ...