UFE Deploying and launching a packaged build on Linux fails due to invalid directory

UE - Platform - Linux - Dec 22, 2016

Deploying and launching a packaged project, using a Custom Launch Profile that is set to copy the project to a repository, fails due to a missing /. I do not see this issue when running a Quick Lau ...

UnrealFrontend doesn't package client and adds both -noclient & -client argument when both server and client is selected to be packaged in same profile

UE - Platform - Apr 15, 2022

Repro Ratio: 4/4 Regression tested in //UE5/Release-4.27.2 CL-18416816 and this issue DID NOT happen. When looking at the log output of the Project Launcher, the command that is ran is:-ScriptsFor ...

In BP/Python Editor Utilities, function SetEditorProperty() unexpectedly fails for Actor Reference Properties on External Actors.

UE - World Creation - Worldbuilding Tools - May 19, 2024

As part of the Python and Editor Scripting Tools, it is possible to programmatically set variables in actor instances of the current level just like when using the Details Panel in the Level Editor. ...

Python function unreal.AssetRegistry.get_assets_by_class is broken

UE - CoreTech - Nov 21, 2022

Repro Rate: 3/3 This issue was reproduced in //UE5/Release-5.1 at CL 23058290. This is confirmed to be a regression since the errors do not occur on the previous version and is regression tested o ...

RootMotion Malfunctioning When Played in Lower Framerates

UE - Gameplay - Player Movement - May 2, 2016

Root Motion Animations are not functioning correctly during lower frame rates. For example, a character moving forward 2 meters at regular frame rate will move 10 meters at a lower frame rate. Regr ...

Crash when travelling during ability activation when URL contains "#"

UE - Framework - Jul 18, 2025

This issue is related to [Link Removed], where the "?listen" option sent on the URL to clients could cause issues with RPCs being called locally during travel. The fix to remove the "?listen" option ...

If a function that takes a custom struct as a parameter is changed and a hot reload performed, any variables in Blueprints that are of that custom struct type will disappear and no longer be usable.

UE - Gameplay - Blueprint - Aug 27, 2015

After creating a custom struct in C++ and adding a variable of that struct type to a Blueprint, hot reloading a code change that involves altering a function that takes the struct as a parameter res ...

Blueprint Struct associations in Blueprint hierarchy causes command line cooker to crash

UE - Gameplay - Blueprint - Oct 13, 2016

If a user creates a specific Blueprint hierarchy with a Blueprint struct, it can cause a issue when the Blueprint struct is being cooked. User description of Blueprint(s) and Blueprint Struct relat ...

Ribbon Particle Normals are reversed from default Sprite Particles

UE - Graphics Features - Oct 13, 2015

It appears that the Vertex Normals from Ribbon Particles are opposite of what is expected via the Default Particle System given both systems share the same alignment (Facing Camera) [Image Removed] ...

While mouse dragging a Spinbox Widget, it cannot be edited once the player's focus is lost (calling: Set Input Mode)

UE - Editor - UI Systems - Nov 28, 2017

The Spinbox Widget cannot be edited if the Player's focus is lost. I have tried using different keyboard letter inputs in the Blueprints and have gotten the same results. ...