Control Rig - Undo doesn't function correctly with proxy and multi bone controls

UE - Anim - Rigging - Control Rig - Oct 26, 2025

Issue from my Technical Animator where the undo operation in Control Rig doesn't work as expected on Proxy Controls. He has recreated the issue using the "Control Rig Samples Pack" and recorded a vi ...

FDetailGroup::AddGroup does not correctly apply the default expansion state for DetailGroups

UE - Editor - Verse Class Editor - Feb 10, 2026

There 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 ...

Adding to Struct causes 'Inappropriate Outermost' warnings

UE - Gameplay - Blueprint - Jun 2, 2015

Adding to Struct causes 'Inappropriate Outermost' warnings to be spammed to the Output Log ...

If PIE is paused using the 'Pause key', the Pause or Resume buttons on the toolbar will no longer start PIE

Tools - Feb 5, 2015

If PIE is paused using the 'Pause key', the Pause or Resume buttons on the toolbar will no longer start PIE. You have to make sure that the icon is toggled to Pause, select the viewport, and then p ...

Sound Mix Modifiers do not properly affect Sound Class

UE - Audio - Mar 30, 2015

Sound mixers do not properly override variables within a sound class. This prevents users from being able to modify variables such as volume or pitch quickly and efficiently by using the push/pop st ...

Changing code based component category causes component to become ineditable in blueprints

UE - Gameplay - Blueprint - Mar 27, 2015

When a component written in code has it's category setting changed in blueprint the rest of the details for that component will not be editable once the component is deselected and reselected. ...

Random Number Generated in Constructor Returning Different Value on Begin Play

UE - Gameplay - Jan 13, 2016

When generating a random number using FMath::RandHelper() in the constructor of an actor, attempting to print that same number on BeginPlay returns a different value than the constructor. However, ...

D3D validation error about resources being deleted while in use

UE - Rendering - Architecture - RHI - Jun 7, 2022

We believe this is a bug in the D3D validation layer, rather than an actual error in our code. We're in touch with Microsoft about it, but I'll make this ticket to track the progress of that investi ...

[MetaSounds] - Trigger inputs called by Execute Trigger Parameter refire on MetaSounds that become active after virtualization

UE - Audio - Aug 31, 2023

If trigger execute is called in Blueprint, it will fire every time the sound recovers from being virtual, even if it has not been called again. See video example: [Link Removed] Also occurs in Re ...

Physical materials cannot be queried

UE - Rendering - Architecture - Materials - Feb 12, 2015

Physical materials placed on starter content shapes always return as invalid for any trace or collision query. ...