r.Shaders.Optimize=0 crashes when compiling a UI material

UE - Rendering Architecture - Materials - Sep 2, 2024

[2024.08.30-22.12.22:384][ 73]LogWindows: Error: appError called: Assertion failed: CurrentGPUVirtualAddress != 0 [Link Removed] [Line: 659] Disabling shader optimisation can crash the editor when ...

When very far out from the map origin, large static mesh is not streaming in until player is close in world partition even though it's within loading range.

UE - World Creation - Worldbuilding Tools - World Partition - May 7, 2025

Context World Partition has a distance-based level streaming system that provides a complete solution for large world management. Problem The problem is that when the player and large static mesh a ...

Texture reprojection from one plane to another produces displacement map with a pattern

RS - Texturing - Mar 4, 2025

Found in 1.5.1.118081 Project: [Link Removed] Message from customer: "The problem occurs when using the texture reprojection tool on a surface scan to bake model details onto a simple bake plane ...

AnimNotify Issue with LevelSequencer Actor with URO

UE - Anim - Runtime - Anim Blueprints - May 19, 2025

Sometimes AnimNotify does not fire when an animation is executed under the following conditions. 1. The CharacterMesh's AnimationMode uses UseAnimationAsset 2. CharacterMesh's URO is enabled (Enable ...

GAS: GameplayEffect with RemovalTagRequirements in networked play triggers FScopedActiveGameplayEffectLock ensure

UE - Gameplay - Gameplay Ability System - Nov 3, 2023

Reported by multiple users. When in a networked session a GameplayEffect is automatically removed due to:a tag being added that's not allowed, or (TargetTagRequirements.RemovalTagRequirements.MustHa ...

Outliner eye toggle fails to hide static meshes when Affect Indirect Lighting While Hidden is enabled

UE - Rendering Architecture - Nov 5, 2025

When a static mesh has the property Affect Indirect Lighting While Hidden enabled, toggling its visibility via the Outliner eye icon does not hide the mesh in the editor viewport. The actor remains ...

UMG Retainer Box renders incorrect colors with Color Vision Deficiency enabled

UE - Editor - UI Systems - UMG - Aug 27, 2025

When using a Retainer Box in UMG with Color Vision Deficiency enabled, the content inside the Retainer Box is rendered with incorrect colors compared to the rest of the UI. This bug is present in UE ...

Deprecated blueprint variable fixups may fail depending on loading order

UE - Framework - Blueprint - Mar 7, 2024

There is currently no simple way to do a deprecated variable fixup on native variables that are set by a blueprint class. For a simple variable rename, CoreRedirects can be used and will work proper ...

In 5.6, bWarningsAsErrors does not work with clang

UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2025

In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes:    [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...

Actors unrelated to the changelist being validated cause errors

UE - World Creation - Worldbuilding Tools - World Partition - Nov 22, 2023

When validating a changelist, unrelated errors to the changelist can appear. Here's an example of running the validation on a cl named "temp cl" which just contains a single actor "Cylinder". The A ...