Unexpected Collision Response When Nesting Primitive Components with auto-weld enabled and physics disabled on children. The root primitive falls through floor even though it is set to block all.

UE - Simulation - Physics - May 27, 2025

Context Auto-weld makes it so if a child is attached to a parent, the two bodies will be joined into a single rigid body. Physic settings like collision profile and body settings are determined by t ...

Upgrading to from 4.6 to 4.7 can cause assets to not be fully loaded in

UE - Gameplay - Blueprint - Mar 8, 2015

A user has upgraded their project from 4.6.1 to 4.7.2 and now one of their assets is partially loaded. After a bit of digging I found an error in the event graph of the ShadowHerosHUD. The nodes are ...

Setting size of GameViewportClient gives different results on Android than in Editor

UE - Platform - Mobile - Feb 9, 2017

Setting size of GameViewportClient gives different results on Android than in Editor OpenGL ES renders with the viewport origin in the bottom left, so that's potentially related to the problem. A ...

Construction script not updating HISM array count

UE - Gameplay - Blueprint - Mar 27, 2017

Construction script not updating HISM array count, even when new elements are adding inside of the level. Regression: Issue occurs in 4.15.1 of the binary build Using the same repro steps provid ...

Incorrect values from NAND node with 3 inputs

UE - Gameplay - Blueprint - May 2, 2017

The values printed from the nand boolean node display incorrect values for the specific set-ups with 3 inputs that are in the repro steps. The node works as intended with 2 inputs, and with some of ...

World Outliner selection does not update transform widget location during play

Tools - May 23, 2017

World Outliner selection does not update transform widget location during play. This issue can be easily fixed simply by reselecting the object, this issue only affects the first time the object is ...

[CrashReport] Mac crash - UE4Editor-SlateCore.dylib!SWindow::IsVisible()

UE - Platform - Apple - Oct 12, 2017

This is a trending Mac crash coming out of the 4.18 previews. Most of the project titles experiencing this crash mention "AR" It is the exact same callstack and crashgroup as [Link Removed], but th ...

Particles Do Not Obey Lighting Channels

UE - Niagara - Apr 17, 2018

Particle systems ignore lighting channels - no matter what channel a light is on (even if no channels are selected), it will affect lit particles. Changing lighting channels on the particle itself h ...

Editor Shortcuts stop working if the editor is launched with a non-Latin-based language

Tools - Nov 4, 2019

Editor shortcuts will not work if you launch the editor with a non-Latin-based language (ex. Russian, Chinese).  The editor must be closed and restarted with English (or possibly any Latin alphabet- ...

fbx attribute curve import do not support correctly tangent at the start end end of the curve

UE - Editor - Content Pipeline - Import and Export - Sep 2, 2020

We are not reading all the key flags and we do not import correctly start key and end key tangent. I create a shelve but this is not the complete fix, we must do this only if we do not have fbx ket ...