Internal Compiler Error: Tried to create a property Crash in scope Beta_C, but another object (ObjectProperty /Game/Alpha.Alpha_C:Crash) already exists there.

UE - Gameplay - Blueprint - Oct 31, 2019

After fixing the crash from [Link Removed] when compiling the child blueprint that has claimed the component name the parent was previously using without having compiled the parent, an internal comp ...

Sublevels Move To New Subfolders Automatically When New Ones Are Made

Tools - Mar 11, 2020

When adding a new subfolder in the Levels window all the sublevels in that parent folder move to the new sublevel. Currently you have to create all the sub folders then move the sublevels to keep th ...

SSR Experimental Denoiser crashes when enabled using Vulkan

UE - Graphics Features - Apr 27, 2020

Enabled the SSR Experimental Denoiser using Vulkan causes the Engine to crash. This crash does not happen with DX11 or DX12. This happens on Linux and Windows (-vulkan). This was reported and teste ...

Clion isn't recognized on Linux

UE - Platform - Linux - May 4, 2020

Setting CLion as the default IDE causes Unreal to not recognize it as a compiler. You are unable to compile C++ projects or create new ones with it set this way. This was reported and tested in 4. ...

Widget Slider increments in an odd way when it is dragged outside of its bounds when next to another Widget

UE - Editor - UI Systems - Aug 6, 2020

The attached video shows the results of this bug. When two Widgets are next to each other and one of them has sliders, when the sliders are dragged past their bounds they will increment backward so ...

Back-face culling not working when translucency is set to Ray Tracing

UE - Graphics Features - Lumen - Oct 23, 2020

While enabling Ray Tracing from the start of the project, when user sets GlobalPostProcess Translucency to Ray Tracing, the back-face of the plane is not culled. However, when the translucency is se ...

FScriptMapHelper::HasKey() and FScriptSetHelper::HasElement() fail on new keys with a substring of another key

UE - Editor - Workflow Systems - Jan 27, 2022

Duplicate key checking in maps and sets in the editor is done via calls to FScriptMapHelper::HasKey() and FScriptSetHelper::HasElement(), but this code is checking for object names which are subsets ...

CopyFileUnderSourceControl Fails on Already Resolved Files

UE - Editor - Workflow Systems - Apr 12, 2023

CopyFileUnderSourceControl has instances when the response is not a success even though the files are copied successfully under source control. It seems FPerforceCopyWorker::Execute() tries to reso ...

Chaos Vehicle does not make them CCD

UE - Simulation - Core - Jan 10, 2024

AWheeledVehiclePawn class tries to use CCD in the constructor, but Mesh->BodyInstance.bUseCCD = true this code does not work to activate CCD because Physics Assets could not be available at this ...

UDataTableFunctionLibrary::AddDataTableRow() fails for blueprint-defined row structure types

UE - Framework - Blueprint - Feb 2, 2024

The editor-scripting blueprint node "Add Data Table Row" fails when the Data Table uses a Row Structure that was defined in blueprint. Internally, it checks if the passed-in UScriptStruct is derived ...