Interaction between sublevels and LevelSequences can break actors attachments hierarchy of the sublevel.

UE - World Creation - Worldbuilding Tools - Aug 6, 2025

Having a LevelSequence opened and unhiding a sublevel can break the attachment hierarchy of the actors that are inside the sublevel. This also affects to the sublevel asset itself. ...

[Interchange][FBX] Import of custom collision add the collision mesh material slot to the mesh material slot

UE - Editor - Content Pipeline - Import and Export - Jan 20, 2025

cf part 2 of that UDN https://udn.unrealengine.com/s/question/0D5QP00000rP4CG0A0/interchange-custom-collision-changes-from-fbx-pipeline?fromCase=1 ...

Using the Set Position in Viewport changes anchor values to 0

UE - Editor - UI Systems - Dec 15, 2017

When Using the "Set Position in Viewport" it changes anchor values of a widget to 0. This node seems like this should not be changing the anchor values, but it is unsure if this is intended behavior ...

USD Stage Import - Spawned actors by USD importer are not saved in level

UE - Editor - Content Pipeline - USD - Jul 20, 2023

we ran into an issue with USD Importer plugin for Unreal 5.2. When you import a USDStage with the "actors" import option - which respawns the newly imported actors into the current level.  However, ...

UnrealMatch3 ensures when launching on iOS

Docs - Samples - Aug 21, 2016

While running regression pass, found that UnrealMatch3 hits an ensure when user selects to Launch on to iOS device. LogOutputDevice:Error: The ini file '../../../UnrealMatch3/Saved/Config/IOS/Device ...

Actors in 4.16 do not enter a resting state when expected

UE - Simulation - Physics - May 17, 2017

There is extra random bouncing that can last a couple of seconds that does NOT occur in 4.15.2. Sometimes the cube would look like it settled, then randomly pop and bounce again. This happened on b ...

Blocky terrain artifacting on iPadPro

UE - Platform - Mobile - Dec 23, 2015

When moving the camera, the surface of terrain becomes very blocky on the IpadPro (9.1.0) The licensee reports this also happens without Metal This didn't occur the iPad Air2 (9.0.2) here using th ...

Volumetric Light Fog Leak through objects

UE - Graphics Features - Dec 31, 2018

Any environment with volumetric fog enabled will have a light leak which appears through objects.  Found in 4.20 CL# 4369336, 4.21 CL# 4613538, 4.22 CL# 4666322 ...

Deleting audio subtrack deletes the entire track

UE - Anim - Sequencer - Jan 20, 2017

Noticed that deleting audio subtrack deletes the entire track. This also appear to happen to affect any property on the track. If I make it inactive or lock it that property applies to each subtrac ...

Memory Use Steadily Increases in Editor With No Tabs Open

Tools - Nov 24, 2015

When in the editor, the memory use steadily increases ~1mb/s and rises indefinitely. This occurs without having any tabs open, and without performing any actions in the editor. Found in 4.10 Binary ...