In editor, sub level instance's streaming state persists incorrectly after toggling Level Behavior without saving

UE - World Creation - Worldbuilding Tools - Level Instances - Jun 11, 2025

When adding a sub level with world partition streaming to a main level where the streaming is also enabled, setting* Level Behavior* of the sub level to Standalone, and saving the result, in the fir ...

iOS Shipping Build using std::thread crashes on launch

UE - Platform - Mobile - Jun 2, 2017

A user is reporting that using the following code in a GameMode class causes shipping iOS packages to crash on launch:void ANOGSSDKGameModeBase::StartPlay() { std::thread([](){ std::clog << "THRE ...

BuildPatchTool doesn't finish if enabled building Http Chunk on Mac

Portal - Jan 25, 2021

We may fix this issue by the following codes. FPakPlatformFile::FPakPlatformFile(): LowerLevel(NULL) ,bSigned(false) { // remove //FCoreDelegates::GetRegisterEncryptionKeyMulticas ...

UGameplayStatics::SpawnEmitterAttached keeps relative location when SnapToTarget is used.

UE - Gameplay - Aug 10, 2016

UGameplayStatics::SpawnEmitterAttached will keep relative position when using SnapToTarget. ...

Framerate drops when using SceneCaptureComponents with a RenderTarget in VR

UE - Platform - XR - May 14, 2018

Using SceneCapture in packaged VR projects causes poor performance. Also observed with SceneCaptureCube Does not occur in 4.18 ...

r.MobileContentScaleFactor appears to be ignored defaulting to 1 on Mobile Devices

UE - Platform - Mobile - Feb 28, 2022

r.MobileContentScaleFactor = 0 should return Native Resolution; 1 should return Standard definiton; 2 shold return an High Definition Resolution. It seems that r.MobileContentScaleFactor is being i ...

Blueprint diff tool does not highlight differences when a change is made to a property in a component

UE - Gameplay - Blueprint - Jun 20, 2018

When making changes to a property in a component of a Blueprint, those changes are not highlighted when looking at the changes in the Components section of the Blueprint Diff tool. ...

Cumulative Patching does not work with Pak signing

UE - Foundation - Feb 20, 2024

Cumulative patching is implemented by copying the generated pak files during staging of the base and each patch to the Releases directory. When creating a patch, all of the pak files from the releas ...

Copied references to Texture2D assets are not formatted correctly when the .csv containing those references is made into a Data Table asset in the Engine.

Tools - Feb 26, 2015

Importing a .csv file that contains references to assets in the project requires the user to copy the references for each asset again before they will work correctly. The references do not need to b ...

Component inheritance does not appear to be consistent when running a project with the -game command line argument

UE - Gameplay - Blueprint - Jan 19, 2018

Component property inheritance sometimes does not behave as expected when opening a project with the -game command line argument. Attempting to load a child Blueprint through code may not correctly ...