Depth reading features on devices without framebuffer fetch are relying on undefined behaviour.

UE - Platform - Mobile - Oct 26, 2016

For devices without framebuffer fetch we are relying on undefined behaviour for depth reading with decals, mod shadows and depth reading materials. (ES2 spec: 3.8.6 Texture Framebuffer Attachment). ...

Using xcode-select to switch between Xcode 10 and Xcode 11 beta can cause Xcode 11 to be unrecognized by the editor

UE - Platform - Apple - Jul 16, 2019

After switching from Xcode 11.0 Beta 3 (11M362v) to Xcode 10 (10A255) and then back to Xcode 11, the editor no longer recognized that Xcode was installed on my machine when trying to use Xcode 11 as ...

Instanced Static Meshes ignore max World Position Offset Displacement for bounds after UpdateInstanceTransform is called

UE - Graphics Features - Jun 18, 2025

When an Instanced Static Mesh Component (ISMC) uses a material with a non-zero Max World Position Offset Displacement, the bounds are correctly expanded at initialization. However, after calling Upd ...

[5.4+] World Partition Landscape Spline Meshes Builder - Source landscape splines are not properly removed/hidden

UE - World Creation - Worldbuilding Tools - HLOD - May 30, 2025

LandscapeSplineActors and LandscapeSplineMeshesActors are not behaving as expected in 5.4 or 5.5. Testing in 5.4 the issue mostly seems to stem from issues with the Target Landscape -> Landscape Ac ...

Event Tick is not running once packaged

UE - Gameplay - Components - Jul 20, 2015

Event Tick works when it's running on Windows however once it's packaged or even launched onto all platforms, the event tick does not work as anticipated. This happens on all platforms. *Project ca ...

Behavior of configuration file hierarchy is different from document

UE - Foundation - Core - Nov 6, 2015

Licensee reported behavior of configuration file hierarchy is different form document here (https://docs.unrealengine.com/latest/INT/Programming/Basics/ConfigurationFiles/index.html) Doc: 1. Engine ...

CapsuleComponent Shape sometimes reverts to previous value after entering a new value

UE - Foundation - Core - Nov 28, 2014

If you manually type in the value for Capsule Half Height, it will sometimes revert back to it's previous value upon hitting Enter. The CapsuleComponent's shape in the Blueprint's Viewport adjust to ...

Unable to launch project from Visual Studio using installed engine build

UE - Foundation - Build - Farm - Feb 23, 2017

When a code project's engine association is switched to a local binary version of a source engine, the project will fail to open from within Visual Studio. Error message says that UE4Editor-Project ...

Python crash the engine at exit.

UE - Editor - Workflow Systems - Oct 25, 2022

A UDN reported various crashes at exit in the embedded Python library. I was able to repro the issue in Release-5.1 and trace it back at the point where python runs its garbage collection in Py_Fina ...

Editor hits Asserts when trying to use debug rendering such as ShowFlag.LODColoration

UE - Rendering Architecture - RHI - Sep 22, 2020

The assert in BasePassRendering.cpp:693 fires, crashing to desktop when using this console command in the editor, in PIE, and closes out the window when playing in Standalone. Does not crash when us ...