Half precision is not supported for OpenGL ES 3.1 Pixel Shaders

UE - Platform - Mobile - Apr 6, 2018

Fix the cross compiler so half precision is supportedAdd a project setting to specify the default precision to support on ES31. Be sure the shader version takes this setting into account. — User des ...

LevelStreamingPersistence: BP added components don't persist properties in PIE until map actor resave

UE - World Creation - Worldbuilding Tools - Mar 6, 2026

Context The LevelStreamingPersistence plugin can be used to remember and restore properties on actors, components and other objects that are part of a streamed level. Persisted properties are resto ...

LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion

UE - Anim - Runtime - May 27, 2023

When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion.  (ie. if the first child pose's blend weight i ...

Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances

UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026

When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...

Editor crashes if an interface array variable is reset in the Detail's Pane

UE - Gameplay - Blueprint - Apr 27, 2016

The editor will crash if an array of interfaces is reset using the "reset values" button (yellow arrow) in the Detail's Pane of the editor. Frequency: 4/4 Crashreporter: N/A Regression? (No), is ...

Client Gameplay Effect stuck on due to duplicate ReplicationIDs

UE - Gameplay - Gameplay Ability System - Oct 31, 2025

We've been tracking down a problem recently with the Gameplay Ability System where a gameplay effect is properly removed on the server, but the client has the gameplay effect stuck on permanently. ...

Templated enum GetValueAsString function returns incorrectly formatted string

UE - CoreTech - Aug 19, 2020

For many years there has been a static function on UEnum called GetValueAsString which would convert an enum like EAttachmentRule::KeepWorld to the string "KeepWorld", if you passed in the explicit ...

GAS: Mixed replication mode and error in MinimalReplicationTags code

UE - Gameplay - Gameplay Ability System - Apr 6, 2022

We're on 4.25.4. We recently turned on mixed mode replication for GAS, which seems to work fine and reduce bandwidth as expected. However one of our unit tests started failing with this error messag ...

[AI] Gaps between Nav Mesh tiles in World Partition map causing movement issues

UE - AI - Navigation - Nov 4, 2025

Navmesh has seams between some tiles that are actual edges rather than previously found "gaps" where it was a debug rendering issue. Pathfinding does fail between these tiles to go straight across. ...

[CrashReport] Mac crash - UE4Editor-Slate.dylib!FTextLayout::GetAsTextAndOffsets()

UE - Platform - Apple - Aug 15, 2017

This is a trending Mac crash in 4.17.0 that also had some occurrence in 4.16. Users have not provided any descriptions of their actions when the crash occurred, but the callstack is nearly identica ...