Sequencer : Attaching a Possessable to multiple Spawnables across multiple cuts causes incorrect location restoration

UE - Anim - Sequencer - Nov 12, 2021

Regression No, according to affects versions 4.27 and 4.27.1 The restore process proceeds in the following order : 1. Remove spawnable actor in first cut (no effect because the actor is already r ...

"FVector contains NaN" on packaged builds for Debug configuration

UE - Graphics Features - Lumen - May 6, 2022

Customer Provided Description:This was experienced in UE 5.01 - custom installed engine (No changes to UE code, simply added the Debug build configuration, see the following command): "c:%ue_dire ...

GAS: GameplayCueNotify OnActive executed twice for Duration GEs on Standalone+ListenServer

UE - Gameplay - Gameplay Ability System - Aug 2, 2023

When playing Standalone or as Listen Server, whenever a GameplayEffect with a duration is applied that fires gameplay cues, the server will locally execute OnActive twice on GameplayCueNotify_Actors ...

Actors disappearing after saving a large number of modifications to world partition maps

UE - Editor - Workflow Systems - Nov 4, 2022

From Licensee: "We've encountered a world partition bug where newly created actors go missing in the viewport and Outliner after saving modifications to a large number of actors. This bug is partic ...

Half precision is not supported for OpenGL ES 3.1 Pixel Shaders

UE - Platform - Mobile - Apr 6, 2018

Fix the cross compiler so half precision is supportedAdd a project setting to specify the default precision to support on ES31. Be sure the shader version takes this setting into account. — User des ...

Add support for motion data on SteamDeck (Steam Controller plugin)

UE - Gameplay - Input - Mar 7, 2025

We have a UDN user with a proposed change: https://udn.unrealengine.com/s/question/0D5QP00000yo70w0AA/add-support-for-gyro-motion-data-to-steam-controller-plugin?fromCase=1 Hi, we were adding gyr ...

LevelStreamingPersistence: BP added components don't persist properties in PIE until map actor resave

UE - World Creation - Worldbuilding Tools - Mar 6, 2026

Context The LevelStreamingPersistence plugin can be used to remember and restore properties on actors, components and other objects that are part of a streamed level. Persisted properties are resto ...

LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion

UE - Anim - Runtime - May 27, 2023

When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion.  (ie. if the first child pose's blend weight i ...

Prevent unnecessary rebuilds of windows resource files

UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2023

How Necessary are BUILT_FROM_CHANGELIST and BUILD_VERSION in Resource Files? We've been investigating ways to improve the speed of our iterative engine builds, and have found that the vast, vast maj ...

Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances

UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026

When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...