Mobile Previewer: Safe Zone Invalid Until Window Resize

UE - Platform - Mobile - Jul 12, 2021

When the Mobile Previewer loads, the Safe Zone widget is not working properly at startup, and requires a window resize to update to the correct Safe Zone. ...

Procedural Mesh Component Memory leak when destroyed from an Array

UE - Gameplay - Oct 15, 2018

When destroying an Actor with a Procedural Mesh Component; that is stored in an Array Variable, the memory for that Actor's Procedural Mesh Component is not cleared, leading to a Memory Leak. Howeve ...

Editor not properly handling frame ranges for 60fps animations

OLD - Anim - May 21, 2015

The editor does not seem to be handling frame ranges properly for 60fps animations. Say you have a 200 frame animation that spans frame 0-200. Upon import it will be 201 frames. If you set the ra ...

A project using the Script Plugin will not open in a binary version of the Engine that is created from an Engine built from source code

UE - Foundation - Build - Rocket (Installed Engine) - Feb 1, 2017

Trying to open a project that uses the Script Plugin in a binary version of the Engine that has been created from an Engine built from source code will fail. The Engine is looking for the file Unrea ...

Local binary build fails for iOS platform.

UE - Foundation - Core - Oct 5, 2017

Attempting to create a local binary build of the Engine for the iOS platform using BuildGraph is currently failing. While trying to build UHT for Mac using a remote build, the build fails because it ...

Custom UVs don't store information properly in layered materials.

UE - Rendering - Architecture - Materials - May 9, 2022

[Link Removed] I have this set up so that FX artists can stack UV manipulations, so I don't want to just have all the UV manipulation in the layer with the base color, even though that does give me ...

A partially broken Geometry Collection ends up with garbage CollisionGroup data that can lead to strange behaviors

UE - Runtime - Deformable - Apr 27, 2025

A partially broken Geometry Collection (GC) ends up with garbage CollisionGroup data that can lead to strange behaviors. The licensee has noticed that a GC that goes thru a field applying ExternalS ...

Crash caused by a race condition in Nanite::DispatchBasePass()

UE - Rendering - Graphics Features - Nanite - Feb 25, 2026

Nanite::BuildShadingCommands() launches two asynchronous tasks: ShadingCommands.SetupTask ShadingCommands.BuildCommandsTask BuildCommandsTask is responsible for modifying ShadingCommands.Commands ...

Bake To Control Rig produces empty keys when rig uses Import Skeleton in Construction Event and binding is a spawnable in a subsequence

UE - ACT Character - Control Rig - Aug 28, 2026

Bake To Control Rig fails to key procedurally-created controls when all three of the following are true:The Control Rig creates its hierarchy at runtime via Import Skeleton in the Construction Event ...

MetalRHI Asserts When Using "Profile GPU" With RHI-Thread/Parallel-Execution

UE - Graphics Features - Sep 14, 2016

When the RHI thread is enabled (with or without parallel-execution) for Metal it isn't currently possible to run "profilegpu" because the GPU timestamp emulation code isn't multi-thread safe and pro ...