Runtime virtual texture sometimes shows corrupted tiles

UE - Rendering Architecture - Apr 28, 2025

Some licensees have reported seeing intermittent corruption of runtime virtual texture tiles. This hasn't been reproduced at Epic. Usually this shows up as some small percentage of rendered tiles l ...

Numerous LogMetal: Warning: AsyncCopyFromBufferToBuffer on overlapping ranges Warnings

UE - Graphics Features - Mar 13, 2018

Numerous LogMetal: Warning: AsyncCopyFromBufferToBuffer on overlapping ranges Warnings Warnings do not appear to be linked to any visual/performance problems in the editor. Could be safely ignored. ...

Inherited Blueprint component template data is not being validated on save.

UE - Gameplay - Blueprint - Sep 8, 2022

UBlueprint::IsDataValid() does not currently check component templates inherited from a parent Blueprint class asset's SimpleConstructionScript; only the current class hierarchy is considered. Given ...

Instanced Static Meshes Incorrect Normals when Scaled Non-Uniformly

UE - World Creation - Worldbuilding Tools - Foliage - Apr 2, 2015

When comparing the World Normals of an Instanced Static Mesh being scaled non-uniformly to that of a regular Static Mesh, their normals do not match one another. I have attempted to look over the d ...

Sequencer animations using Skeletal Mesh Pose don't play properly if following another sequence with an animation using Keep State

UE - Anim - Sequencer - Feb 20, 2019

The bug affects skeletal mesh animations when played in sequencer with AnimBP after another animation which was set to Keep State. This is a follow-up to [Link Removed]. Two animations now play cor ...

Replication issues & warnings if a client hitches while the server seamless travels

UE - Networking - Jul 28, 2020

If a client hitches while a server performs a seamless travel, the client will get multiple lines of logspam of these warnings:Warning: UActorChannel::ProcessBunch: SerializeNewActor failed to find/ ...

Undo then Redo Creating a Spawnable in Sequencer Creates Extra Actor in Level

UE - Anim - Sequencer - May 3, 2023

There is a bug when performing an undo/redo on pasted or spawned actors in Sequencer.  It appears that the transaction system is re-creating an actor on redo, but Sequencer doesn't see that, so it ...

Reflection capture doesn't work when using Lumen GI and SSR

UE - Rendering Architecture - Mar 24, 2025

Reflection Capture does not appear to work with Lumen + SSR. Licensees have reported that there are cases where they want to combine Lumen GI, SSR and Reflection capture for quality and performance ...

Source Control: Perforce Branch History is Parsed Incorrectly

Tools - Sep 26, 2016

Several issues have been reported within the ParseHistoryResults method from PerforceSourceControlOperations: 1. Any Records that share the same filename will only display the last record with that ...

Extremely long Spline Point will cause the editor to lose FPS

Tools - Nov 13, 2015

Extremely long Spline Point will cause the editor to lose FPS and crash some machines User Description: A couple of times I've accidentally scaled a spline node to be huge, causing the spline to ...