Blueprint Launches onto tvOS fail during runstep: Error_DeviceOSNewerThanSDK

UE - Platform - Mobile - Apr 19, 2019

When a user launches blueprint project to a tvOS device they will fail to run the project during the run step and if they manually try to launch the app from the dashboard. This issue does not repr ...

Assets on paths with speed parameters are sped up in Path Tracer exports

TM - Tools - Jul 18, 2025

Reported in SF [Link Removed] In Path Tracer renders, all paths with a speed component (vehicles, bicycles, custom) will render at an increased speed than specified in the exported render. This is ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

Property Editors fail to import text values for FKeys within array/set/map containers when the key is identified by some valid non-alphanumeric characters

UE - Gameplay - Input - Oct 28, 2024

The FKey structure represents a user action input such as a keyboard key, a mouse button/wheel, or a gesture in VR. For the keyboard, it can represent any pressable key, such as letters, numbers, sy ...

The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors

UE - Simulation - Physics - Destruction - Oct 15, 2024

The Remove-On-Break (ROB) feature, set on Fracture Mode on Geometry Collections (GC), was supposed to make the particle shrink until it vanishes. When the GC goes to sleep the shrinking stops and sh ...

Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage

UE - Niagara - Feb 28, 2025

Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...

Instanced Static Mesh does not apply World Aligned Material correctly

UE - Graphics Features - Aug 22, 2016

If you apply a material that uses World Aligned Blend to an instanced static mesh, it will display differently than an non-instanced static mesh with identical settings. They only look identical if ...

Absolute World Position post process no longer works in mobile preview

UE - Platform - Mobile - Sep 2, 2020

User reports this work correctly in 4.24, but now no longer works as expected in 4.25.I don't have a clear CL just yet, marking unconfirmed. If you change the settings to use ES3.1 Preview and just ...

Orientation setting does not respect user's settings on Android

UE - Platform - Mobile - Feb 25, 2019

The Orientation setting in the editor for Android phones does not respect the user's settings. Despite "Auto-rotate" being turned off, the orientation of the UE4 app will change if it is set to do s ...

Animgraph-Blend node-Alpha Scale Bias-larger values imprecise

OLD - Anim - Jan 21, 2015

When setting the alpha scale bias for a blend node in the AnimGraph, if you set the values so that the difference is greater than 10, the values will not enter as whole numbers (see image.) ...