Compile warning/error in the FUpdateCollisionResponseHelper destructor

UE - Simulation - Physics - Dec 15, 2017

It has been reported that when building with Visual Studio 2017 version 15.5.1, a warning/compile error is shown in BodyInstanceCustomization.cpp: warning C4287: '<': unsigned/negative constant mism ...

CopyTask in BuildGraph never throws an exception if the copy fails

UE - Foundation - Horde - BuildGraph - Feb 28, 2023

CopyFile function in CommandUtils.cs assumes that an exception will be thrown if the number of retries is exceeded, but the loop condition prevents it from being thrown. Following fix works:publics ...

Editor crashes when actors using child actor component are loaded while Static mesh actor filter is enabled in the outliner

UE - Editor - Dec 5, 2022

Reproduced 3/3 times. Unclear whether this is a regression as filter GUI is new in 5.1 for Outliner. ...

When the Initial Position of an Animation Asset is entered outside the expected range, the animation gets stucked and does not refresh.

UE - Anim - Runtime - Mar 18, 2024

The animation gets "corrupted" when the Initial Position value has an invaildad value. In this case, this means that the Initial Position value is outside the range of the duration of the Animation. ...

TSR and TAA history accumulation gets reset when taking viewport screenshots or when clicking outside the tree in the outliner

UE - Graphics Features - May 30, 2025

TSR (and TAA) history accumulation gets reset when taking viewport screenshots or when clicking on an empty area in the outliner (when a tree item is selected). This can cause an undesirable issue w ...

Breakpoints on nodes in deleted functions are not cleared

UE - Gameplay - Blueprint - Nov 16, 2018

Might be a simpler repro than this, but take a look at revision 1 of PreRolledBoxes in FortniteMain to see an asset affected by this. It was duplicated from StoreRoot which had breakpoints in some o ...

Setting size of GameViewportClient gives different results on Android than in Editor

UE - Platform - Mobile - Feb 9, 2017

Setting size of GameViewportClient gives different results on Android than in Editor OpenGL ES renders with the viewport origin in the bottom left, so that's potentially related to the problem. A ...

FAnimUpdateRateParameters::GetInterpolationAlpha appears to be returning an invalid value for TrailMode

UE - Anim - Aug 5, 2023

It appears that  FAnimUpdateRateParameters::GetInterpolationAlpha is not returning a sensible value when running in TrailMode.  Currently the only variable in the calculation is EvaluationRate which ...

Mac - Inconsistent results for Lumen renders

TM - Rendering - Jun 3, 2025

Reported in SF [Link Removed] and [Link Removed] Users on Mac are reporting inconsistent rendering results for Lumen in image exports that do not include any settings changes. When exporting some ...

Simulated physics bodies not working properly with BP Move Component To node

UE - Simulation - Physics - Jun 5, 2015

This issue may reference [Link Removed] which was recently fixed with 4.9 CL-2553675. When using the MoveComponentTo node physics do not work properly compared to other methods to move a component ...