Chained physics constraints do not work correctly when one constraint is limited

UE - Simulation - Physics - Aug 12, 2017

A chain of physics constraints that includes a physics constraint that is set to Limited does not work correctly. When collision occurs, the attached actors start moving erratically. Regression?: N ...

Children of Retainer Box cannot be interacted with when visibility is set to "Self Hit Test Invisible"

UE - Editor - UI Systems - Jun 19, 2017

When there is a Retainer box with the visibility set to "Self Hit Test Invisible" and has children, the children cannot be interacted with. Children such as a button cannot be clicked. This issue c ...

UObjects returned from "Get Item Children" in a TreeView widget causes an engine crash, due to invalid pointers

UE - CoreTech - UObject - Jun 9, 2020

UObjects returned from "Get Item Children" in a TreeView widget causes an engine crash, due to invalid pointers. User has proposed the following fix: The best fix is probably such: When Slate list ...

Crash when using StaticDuplicateObject with mismathced Source and Destination class types

UE - Foundation - Jun 19, 2025

Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...

Static mesh's material slot's cast shadow does not require a build of StaticLight

UE - Graphics Features - Dec 7, 2017

If static mesh's material slot's cast shadow is changed, UE4 does not show "LIGHTING NEEDS TO BE REBUILT". I solved it with the following fixes. StaticMeshEditorTools.cpp void FMeshSectionSettin ...

Building Lighting will Generate Additional Lightmaps after Rotating Lightsource

UE - Graphics Features - Jul 7, 2015

Lightmap sizes seem inconsistent after rotating a light source and rebuilding the lighting. This causes concern about file sizes when packaging the project that is using baked static lighting. The ...

Disabling the Paper 2D plugin causes a packaged project to not open

UE - Foundation - Cpp Tools - Automation Tool - Jun 19, 2017

When working in a project that is in 4.16, disabling the Paper2D plugin causes a packaged version of the project to not open. This issue is different from previous versions as disabling the plugin i ...

Duplicate .so files in GoogleVR.

UE - Platform - XR - Jun 2, 2017

A licensee recently pointed out that there are now several GoogleVR lib files in 4.16 that are present in the Engine twice due to some of them being copied into a subdirectory. For example, , in 4.1 ...

Stencil that has been marked with ResponsiveAA is cleared by DistortionPass

UE - Graphics Features - Dec 14, 2021

From UDN: When an object with ResponsiveAA enabled is in the screen and then an object with Distortion enabled comes into the screen, ResponsiveAA does not work. ​ I guess this is because the Ste ...

Unable to undo editing enum description

UE - Gameplay - Oct 30, 2019

The user is unable to undo the editing of the enum description. The output log and undo history would confirm that the undo was carried out, however it did not do anything in reality. Resetting the ...