Intermittant motion blur issues in content heavy scenes

UE - Rendering - RHI - Jul 30, 2026

When using the following RHI/Render thread/GT sync configuration:r.OneFrameThreadLag 1r.GTSyncType 1 The previous skinning bone data can be corrupted and introduce visual artifacts on everything us ...

User Struct value set through a component is reset to default when modified through the level instance

UE - Gameplay - Jul 3, 2017

Struct value set through a component is reset to default when modified through the level instance. If it's not set through the component, it works fine. User Description: There is a bug in the eng ...

Depth reading features on devices without framebuffer fetch are relying on undefined behaviour.

UE - Platform - Mobile - Oct 26, 2016

For devices without framebuffer fetch we are relying on undefined behaviour for depth reading with decals, mod shadows and depth reading materials. (ES2 spec: 3.8.6 Texture Framebuffer Attachment). ...

Native gameplay tags in plugins are cleared when reading config files

UE - Gameplay - Aug 14, 2024

When references to Gameplay Tags are loaded, it checks to see if they are already registered. If they are not already registered, it will notice it is invalid and may print a warning depending on th ...

Inline retargeting gives different output pose vs retargeting from mesh

UE - CAPT - Retargeting - Nov 19, 2025

When we perform a retarget from an input pose rather than another mesh, the transforms within the anim bp have already been conformed to the target mesh by translational retargeting and compatible s ...

OnActive Gameplay Cues not activating properly in standalone

UE - Gameplay - Nov 28, 2016

This was reported from https://udn.unrealengine.com/questions/323255/bugfix-onactive-not-triggering-for-gameplaycues-on.html In some case it looks like OnActive gameplay cues are not working proper ...

Editor crash on level load when bUseActorFolders is true after dragging Actor into another folder in the Outliner

UE - World Creation - Worldbuilding Tools - OFPA - Mar 7, 2023

From licensee: Hello! Our level streaming setup enables the bUseActorFolders on our levels. When moving the Actor into another folder via the Outline, the editor will crash on the next load Assert ...

Physics Constraints have unexpected behavior when used on nested static mesh components

UE - Simulation - Physics - Jul 5, 2017

Physics Constraints have unexpected behavior when used on nested static mesh components. Simulating inside of the blueprint has a similar effect to what is expected but when the BP is added to the l ...

Level cannot save when compile setting is changed on blueprint present in level

UE - Gameplay - Blueprint - Aug 21, 2017

When using a project that has a blueprint in a level when the project is created, there is an issue that is occurring when you modify the compile settings and attempt to save the level There is an e ...

Interpolators of Particle Dynamic Parameters Need "nointerpolation".

UE - Niagara - Aug 1, 2019

Regardless Niagara or Cascade, dynamic parameters for particles are passed to pixel shaders from vertex shaders via InterpolantsVSToPS. It can cause a precision error on some materials, for example ...