Overridden Interface Functions in Child BPs lose array output pins after closing/reopening the project and become invalid

UE - Gameplay - Blueprint - Feb 7, 2015

Overridden Interface Functions in Child BPs lose array output pins after closing/reopening the project and become invalid. Reproduced in Main //depot/UE4/Promotable-CL-2434822 ...

UMG Throbber is not showing in project when using 'Set Number of Pieces' node off of Event tick

UE - Editor - UI Systems - Apr 22, 2015

If you add a throbber to a UMG Blueprint and use the Graph of the Blueprint to change the 'Set Number of Pieces' and use 'Event Tick' to tick the widget, the throbber widget will not appear on scree ...

Directx12 crashes with OOM

UE - Graphics Features - May 7, 2018

In editor, when running a task that does not issue a BeginFrame/EndFrame for a long time, the GPU will eventually run out of memory.  See UDN: https://udn.unrealengine.com/questions/431450/directx1 ...

Adding/Removing a Material Layer on a Parent Material doesn't propagate to Children correctly

UE - Rendering - Architecture - Materials - Jun 9, 2026

When a Material Layer is added to or removed from a Parent Material the layer changes don’t automatically propagate to Child Materials correctly even if the Parent Material is saved. The Child mate ...

Landscape Materials Layers Show "none" but are Still Able to Paint on Landscape

UE - LD & Modeling - Terrain - Landscape - Jun 15, 2015

Landscape material layers show "none" after generating weight blended layers in landscape paint mode. The landscape layers are painted as normal but do not show that any layer is assigned. ...

LIVE: The Now node (FDateTime::Now) does not return the correct time

UE - Foundation - Core - Nov 18, 2014

The 'Now' node does not return the correct time if ran through a 'Print String'. (NOTE: However, the 'Utc Now' node does return the correct time.) ...

Lighting channels not working as expected when enabling Ray Tracing Shadow

UE - Graphics Features - Lumen - Oct 13, 2020

Non-Ray Tracing Shadows are only cast from lights on meshes assigned to the same Lighting Channel. When enabling Ray Tracing Shadows this is not the case. Lights will still cast Ray Tracing Shadows ...

When Building Light for a SubLevel of a project, BSPs will be built into the level regardless if hidden or not

UE - LD & Modeling - Modeling Tools - BSP - Feb 23, 2016

BSPs will be built with light/shadow extrapolated even if they are placed in a hidden sub_level of the project at the time of building. Also Tested in 4.10.4, 4.11 Preview 6 and Dev-Editor-CL-28772 ...

promoting a variable to a local variable in another blueprint creates compile error.

UE - Gameplay - Blueprint - Sep 30, 2015

If a local variable set variable is copied/pasted over to a second blueprint and the input pin is promoted to a local variable, compiling the blueprint will cause a compile error to appear until the ...

Duplicate slots being created in Anim Slot Manager

OLD - Anim - Dec 11, 2015

Duplicate slots are being created automatically under the Default Group in the AnimSlotManager. This is causing some problems because it replaces the originally created slot with the duplicate in t ...