A Blueprint containing an array Swap node will fail to be nativized.

UE - Gameplay - Blueprint - Jul 17, 2020

Blueprint assets that utilize an array "swap" node to swap elements cannot currently be converted to C++. Current workaround: Either avoid use of the "swap" node or exclude the Blueprint asset from ...

EQS Overlap test no longer recognizes custom Collision Object Channel

UE - AI - Nov 12, 2019

Environment Queries Ignore tests for Custom Collision Object Overlaps. Note: The expected behavior seems to have worked in 4.21, After following the steps to reproduce, I can verify a successful de ...

Alt-tabbing out of a Standalone App or packaged version of a game does not trigger LostFocus or ReceiveFocus

Tools - Sep 9, 2015

If a user uses Alt-tab to change to another window, the ReceivedFocus and LostFocus functions are not called as they would usually be called when using something such as Shift+F1 or Ctrl+Esc. Note: ...

OSVR fatal error while playing in -game

UE - Platform - XR - May 6, 2016

Found on: //UE4/Dev-VR CL-2967563 About 1/6th of the time I'd start a -game instance and go in to stereo on the OSVR, the game would seemingly just close itself. I say close as opposed to crash, si ...

Struct with a single unaltered element will remove the element from the struct on compile

UE - Gameplay - Blueprint - Oct 7, 2015

If used inside a UMG Blueprint, a struct that has only one element will remove the element from the struct after compiling the blueprint. If the element is edited or a second element is added then ...

Blueprints not marked dirty when variables in referenced actors are renamed

UE - Gameplay - Blueprint Compiler - Feb 20, 2018

Blueprints using renamed variable do not indicate that they need to be recompiled. (However errors are shown on play) It is possible to not see an error if you add a variable with the same name as ...

UE-47779 - Crash exiting packaged PlatformerGame while in the Main Menu

UE - Gameplay - Jul 27, 2017

This was occurring when I quit via the Quit button in the Main Menu GUI. I also repro'd this using the "Quit" command in the console. I found this on Linux, but this was repro'd on Mac and Windows ...

Unable to interact or collide with geometry collection after Removal on Sleep or Break timer finishes, yet unbroken piece continue to render

UE - Simulation - Core - Dec 18, 2025

Context: A static mesh is able to have a geometry collection generated from it using the Fracture editing mode. It can be fractured in many different ways, and when acted upon by a chaos field agent ...

Crash opening Infiltrator packaged on Windows for Linux

UE - Platform - Linux - Jan 18, 2017

This occurred on packages that were created on different Windows machines. This crash is not occurring on other platforms during our Samples Pass. ...