Unwanted black boundaries are displayed in a vertical split-screen with 3 players.

UE - Gameplay - Dec 2, 2019

Floating point error from UGameViewportClient::SplitscreenInfo causes this issue. FMath::TruncToInt( 3240 /*ViewportSize*/ * 0.333f/*Ratio in SplitScreenInfo*/ ) = 1079 I suggested a following t ...

Physics Constraint Actor: When plasticity is enabled, Drive Position Target is reset to zero on constraint initialization

UE - Simulation - Core - Mar 5, 2026

When a Chaos joint constraint is first created, having linear/angular plasticity enabled will unexpectedly force its linear/angular drive position target to zero on initialization, disregarding the ...

Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply

UE - World Creation - Worldbuilding Tools - May 4, 2026

Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...

Crash trying to delete an actor after undo/redo adding a component

Tools - Feb 1, 2017

Not a regression as it occurs in 4.14.3 ...

Line height for text boxes does not appear to be affected by scaling when using a scale box

UE - Editor - UI Systems - Jan 12, 2016

When scaling text with a scale box the letter will begin to overlap when scaled up or become really far apart when scaling down (this is referring to the space between the top and bottom of the lett ...

The Tint setting under style for the slider bar in UMG does not appear to have an affect on the color of the widget

UE - Editor - UI Systems - Sep 4, 2015

Changing the Slide bar Color/Slide Handle Color will change the color of the Slider widget. However when changing the "Tint" settings under style, there does not appear to be any color change. ...

5.3 crashes when loading a map with an actor that had the class of one of its components changed

UE - Gameplay - Components - Feb 1, 2024

Create a blueprint based on actor, give it a SceneComponent named ExampleComp (BP_TestActor) - this should be the blueprints only componentCreate a new level (TestMap), place an instance of the bluepr ...

Setting Lightmap Coordinate Index Past 3 Causes Mesh to Get No Lightmap Information

UE - Graphics Features - Nov 20, 2018

Meshes with their Lightmap Coordinate Index set to anything over 4 will not be lit by static or stationary lighting.  Found in CL# 4.19 4033788, 4.20 CL# 4369336, 4.21 CL# 4541578, 4.22 CL# 4573698 ...

Animation Rate Scale does not appear to have an affect when blending an animation with two different Rate Scales

OLD - Anim - Dec 14, 2018

Rate Scale does not appear to have an effect when using a blend space that blends an animation with two separate Rate scales. ...