Nested PackedLevelActor bounds issue

UE - World Creation - Worldbuilding Tools - Level Instances - Jul 23, 2024

UserSceneTexture Post Process Material Renders Incorrectly When ScreenPercentage is Below 100

UE - Graphics Features - Dec 17, 2024

When using a UserSceneTexture in a post-process material, a visible rendering issue occurs if the viewport's ScreenPercentage is set to below 100. This issue looks like it might stem from an incorre ...

LastRenderTime does not update when Occlusion Culling is disabled

UE - Graphics Features - Feb 25, 2025

When disabling Occlusion Culling, Components will not have their Last Render Time updated. ...

If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible

UE - Virtual Production - Tools - Jul 31, 2025

If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible. The behavior only shows after d ...

[AI] StateTree Category = Input validation doesn't validate child properties

UE - AI - StateTree - Oct 10, 2025

Normally if you have a property in your state tree instance data of the input property(Category = Input), when you compile the state tree, you will get errors if the property does not have a binding ...

MultiProcessCook Shader Symbols fail to write when two workers race and try to write them at the same time

UE - Foundation - Data Pipeline - Cooker - Jan 4, 2026

When shadersymbols are requested, cooking shaders writes the symbol files into {Project} /Saved/ShaderSymbols/<PlatformName>. These symbols are written by the function FShaderSymbolExport::Write ...

2 minute hang and high memory usage when adding assets with large textures

UE - Foundation - Core - Cooker - May 28, 2015

2 minute (or more) hang and high memory usage when adding assets with large textures. The memory increase can be up to 3 or 4 GB when none of these assets(or referenced assets) take up nearly that ...

Crash When Adding Actor Component Tagged 'Within' to a Game Mode Blueprint

UE - Gameplay - Components - Apr 25, 2016

Crash occurs when attempting to add an actor component c++ class to a game mode blueprint if the actor component is tagged with the Within="GameMode". Found in 4.11.2 binary, reproduced in 4.10.4 ...

Moving or changing the name of a project's GameInstance will switch the Game Instance Class to None and crash launched games

UE - Foundation - Core - Nov 26, 2014

If the GameInstance set in Project Settings > Maps & Modes > Game Instance Class is renamed or moved to another folder, the Game Instance Class is switched to None. This causes a launched game to cr ...