Launching multiple Editor processes in UE 5.5 can throw warnings due to USD Core plugin initialization

UE - Editor - Open File Formats - USD - Apr 23, 2025

Launching multiple Editor processes at the same time with the USD Core plugin enabled can cause warnings to be logged like the following:LogUsd: Warning: Failed to update LibraryPath for USD plugInf ...

With Accurate Velocities from Vertex Deformation and Instanced Stereo enabled anti-aliasing does not affect the right eye

UE - Platform - XR - Jul 8, 2016

KevinR: Make sure you are using Temporal AA (TXAA), and I was using SteamVR/Vive With Accurate Velocities from Vertex Deformation and Instanced Stereo enabled anti-aliasing does not affect the righ ...

InstancedFoliageActor experiences issues with floating point precision when far away from World Origin and is not affected by Origin Rebasing

UE - World Creation - Worldbuilding Tools - World Composition - Jul 17, 2020

Foliage generated by Landscape Grass Type do not encounter this issue. Only hand painted foliage with foliage tool is not affected by rebased origin. Foliage vibrates when it is located in long dist ...

Get Class Defaults node disconnects output pins when project upgraded from 4.11 to 4.12

UE - Gameplay - Blueprint - Jun 7, 2016

Upgrading a project from 4.11 to 4.12 causes Class Default nodes to disconnect their output pins from other nodes. If the node is reconnected and saved, it will disconnect again when the project is ...

Open Formats: FBX Reimport - Reimport settings for FBX not getting stored

UE - Editor - Open File Formats - Oct 16, 2026

FBX assets originally imported in 5.7 lose their "Combine Static Meshes" import setting when reimported in 5.8. In 5.8 "Combine Static Meshes" was changed from a bool to 3-way enum, and the old bool ...

Shadow Quality regression on mobile for Movable Directional Lights

UE - Platform - Mobile - Oct 11, 2016

Shadow quality from a movable directional light has lower resolution quality than the previous release of the engine. This is a regression in quality from 4.12.5 to 4.13. Tested with: Good Quality ...

Full Screen Native Resolution not supported on new iPad Pro 11-inch and iPad Pro 12.9 inch (3rd generation)

UE - Platform - Mobile - Nov 16, 2018

A licensee has reported that Full Screen native resolution does not work properly on the iPad Pro 11-inch and on the iPad Pro 12.9-inch (3rd generation). Black borders are used around the screen ins ...

Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)

UE - Framework - Dec 19, 2025

This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...

FBX Import - Morph target normals not correctly applied when imported as LOD 0

UE - Editor - Open File Formats - FBX - Nov 27, 2025

This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...

Packaging for HTML5 seems to have grown in package size

UE - Platform - Mobile - Aug 30, 2016

The size of packages for HTML5 has greatly increased since 4.10.4 to 4.11.2 and has since increased. Example: First person template, no starter content - size of whole HTML5 folder once packaged: 7 ...