Certain combined Linear/Angular movements cause Client to freeze for several seconds

UE - Simulation - Physics - May 24, 2019

When using Replicated Movement, certain combined linear/angular movements cause the client to freeze for several seconds and then catch up to the server. This is a regression from 4.21.2 (CL-4753647 ...

RemoveAxisMapping() removes axis mappings of the same key regardless of Scale value

UE - Gameplay - Jun 26, 2019

When you remove an axis mapping using a specific key it will remove all mappings even if they have separate scales. The user found a fix that I verified that worked. In "InputSettings.cpp", which i ...

Behavior of reparenting Component on UE5 is different from UE4

UE - Gameplay - Blueprint Editor - Mar 29, 2022

In UE4, Reparenting the Child Component did not update it on the screen, but the Relative Transform was updated. However, UE5 now retains Relative Transform, so there are on-screen updates. This is ...

Virtual Heightfield Mesh crash using released Vertex Factory

UE - Rendering Architecture - Jul 25, 2023

When using VirtualHeightfieldMesh we see intermittent crashes in FDepthPassMeshProcessor::TryAddMeshBatch(). This can happen when FVirtualTextureProducerCollection::CallPendingCallbacks() is called ...

Affect Indirect Lighting While Hidden can affect the environment after data layer unload in editor

UE - Graphics Features - Sep 9, 2024

After setting Affects Indirect Lighting While Hidden but before saving the level, the emissive contribution persistents through datalayer visibility toggles. This does not appear to occur in PIE, on ...

LODs with screen size 0 in legacy assets are incorrectly converted to 1 on load

UE - Editor - Content Pipeline - Sep 11, 2025

When loading a mesh asset (static or skeletal) created in an old version of Unreal (e.g. 4.10), any LOD whose LOD screen size was originally set to 0, is converted to 1. This causes LODs that would ...

Mac Crashing on Editor Launch

UE - Graphics Features - Sep 24, 2015

User reporting he is crashing when launching the Editor "This is a 4.9.1 binary build (latest), I can't give you the exact version because it crashes on the initialisation stage at 0%. The system i ...

Audio Components ignoring Start Time set by Play node on Android

UE - Audio - Jul 15, 2015

Setting the start time within the Play node for an audio component does not function when deploying to Android. The set up works fine when playing on the PC, and the sound functions on the Android ...

Running a server from the editor will crash this project

UE - Networking - Mar 8, 2015

Running a server from the editor will crash this project. Reproduced by using UE4Editor <projectname> -server -log to run the editor. This does not occur with a new project in 4.7.2 or in Main. ...

Editing Struct variable types can cause pins of an array of that struct to become disconnected

UE - Gameplay - Blueprint - Jun 6, 2016

When changing the variable type of a variable in a struct, it can cause some pins related to arrays of this struct to become disconnected. The project provided was from the Marketplace, entitled "Su ...