Slight delay when switching between UMG buttons on Mac

UE - Editor - UI Systems - Dec 30, 2014

There is a slight delay when clicking between two different UMG buttons on Mac. Tested on OSX 10.10.1. There also appears to be a flicker on the Menu Bar. ...

FBX Export - StaticMesh export to FBX crashes if UVElements has more channels than VertexInstanceUVs

UE - Editor - Content Pipeline - FBX - Jan 22, 2026

As indicated in the repro steps, we have a StaticMesh asset that, for some reason, has a mismatch in their serialized bulk data where:MeshDescription->GetNumUVElementChannels() == 2FStaticMeshConstA ...

Server doesn't process anim notifies with montage tick type set to queued when bad network conditions occur

UE - Characters - Animation - May 3, 2023

After some testing this issue looks to only occur with queued notifies and not with branching point notifies. UDN: https://udn.unrealengine.com/s/question/0D54z00009643x4CAA/server-doesnt-process-a ...

Mass is not calculated if an object's Collision Enabled field is set to No Physics Collision even when Simulating Physics

UE - Foundation - Core - May 22, 2015

If an actor has 'Simulate physics' enabled and the Collision Enabled field is set to anything other than Collision Enabled (i.e. OverlapAll sets this to No Physics Collision) then mass is reset to 1 ...

RenderTarget Texture Alpha rendered incorrectly when SceneCapture2D AA set to true

UE - Graphics Features - Jan 8, 2016

The Alpha Channel of the Render Target Texture is rendered as a value of 1 (solid white) when the SceneCapture2D actor is set to LDR with PP and Anti-Aliasing is set to true in the General Show Flag ...

Using a user generated timeline in blueprint causes an exception in engine code.

UE - Gameplay - May 13, 2015

This crash is caused by an exception that is thrown due to the functions inside of a blueprint based off a user-defined class that is suppose to mimic Timelines. ...

Modulated shadows do not render in the correct area on older devices / versions of Android OS

UE - Platform - Mobile - Apr 5, 2016

This issue was reported by a user who was having issues with their modulated shadows showing up in random spots on their mobile devices. Their devices were a Samsung Galaxy Note 2 and a ASUS Zenfon ...

Crash trying to convert skeletal mesh to Nanite

UE - Rendering - Graphics Features - Nanite - Mar 6, 2025

In SkeletalRenderNanite.cpp / FDynamicSkelMeshObjectDataNanite::UpdateBonesRemovedByLOD, bone indices are of type FBoneIndexType (defined as uint16 from BoneIndices.h), instead of int32. On line 18 ...

Does FSlateElementBatcher::AddCachedElements need to check if r.HDR.UI.CompositeMode is enabled?

UE - AI Workflows - UI Systems - Aug 28, 2024

When a specific configuration of HDR cvars are set, PIE in a New Editor Window will not render the game world. Settings (For DefaultEngine.ini): ```[SystemSettings] r.AllowHDR=1 r.HDR.Display.Color ...

SplineMeshComponent's collision will start to distort the longer the Spline becomes

UE - Gameplay - Nov 30, 2016

SplineMeshComponent's collision will start to distort the longer the Spline becomes This is a regession. It was working in 4.13.2-3172292 User Description: When drawing out a long spline mesh ( r ...