World Partition - Deleted actors can become unloaded prior to saving

UE - World Creation - Worldbuilding Tools - World Partition - Apr 11, 2025

In world partition levels, deleted actors can become unexpectedly unloaded prior to saving, causing loss of work. Specifically, this issue occurs after the undo history has been cleared (either manu ...

Calling UHierarchicalInstancedStaticMeshComponent::AddInstance multiple times causes crash

UE - World Creation - Worldbuilding Tools - Foliage - Jan 16, 2019

Calling UHierarchicalInstancedStaticMeshComponent::AddInstance multiple times causes multiple BuildTrees to be created and run asynchronously at the same time. Tested in 4.21(CL - 4613538) How t ...

Blueprint Struct associations in Blueprint hierarchy causes command line cooker to crash

UE - Gameplay - Blueprint - Oct 13, 2016

If a user creates a specific Blueprint hierarchy with a Blueprint struct, it can cause a issue when the Blueprint struct is being cooked. User description of Blueprint(s) and Blueprint Struct relat ...

FSlateApplication::OnControllerAnalog triggers a MouseLeftClick event to be added to the input stack.

UE - Gameplay - Input - Jun 3, 2016

It appears that FSlateApplication::OnControllerAnalog triggers a left mouse click to occur on mobile platforms. If developers haven't properly avoided hooking up delegates to the InputComponent for ...

Closing the GPU Visualizer window on Linux causes the editor to crash

UE - Platform - Linux - Oct 21, 2015

After opening the GPU Visualizer window, pressing the "X" to close the window causes the editor to crash. ...

Compile failure packaging for iOS: "error: member access into incomplete type 'const FCulture'"

UE - Platform - Mobile - Dec 14, 2016

Compile failure packaging for iOSUATHelper: Packaging (iOS): UnrealBuildTool: D:\Build\joseph.wysosky_QuickSwitch\Engine\Plugins\Online\IOS\OnlineSubsystemIOS\Source\Private\OnlineStoreIOS.cpp(123 ...

Ensure attempting to submit to source control after enabling plugin

Tools - Nov 17, 2016

Ensure occurs when trying to submit to source control after enabling a plugin in the editor. I wasn't able to reproduce this if the uproject wasn't checked out. ...

Blueprint Cannot Give Niagara CPU Access To Skeletal Meshes Added From Blueprint

UE - Niagara - Apr 4, 2019

When a user tries to add a skeletal mesh component to a blueprint with a niagara system to use the skeletal mesh with that niagara system, the niagara system will stop rendering because it does not ...

Custom Primitive Data types do not work with Procedural Meshes even though the option exists in their Details Panel

UE - Graphics Tools - Modeling Tools - Dec 16, 2021

This is a not a regression. Tested in UE5(Binary), UE4(Binary), and UE5 Main(P4). Procedural Meshes have the option for CPDs listed in their details panel under Rendering > Advanced >Custom Primit ...

Missing texture assets cause warnings on editor start: LogStreaming: Warning: Failed to read file '../../../Engine/Plugins/Developer/PlasticSourceControl/Resources/Icon128.png' error.

UE - Editor - UI Systems - Jan 7, 2025

There are a number of missing texture assets which are failing to be read when the editor opens. This is causing a warning to be thrown each time the editor opens, potentially causing CI/CD tests (i ...