Mouse is not captured when running -game on Linux

UE - Platform - Linux - Aug 28, 2017

Launching a game with the -game command causes the game window to not capture the mouse until the window is clicked. Regression: Yes - This behavior does not occur in 4.16.3 (CL 3561208) ...

Discrepancy in capsule distance to floor when crouching

UE - Gameplay - Components - Aug 30, 2017

When crouching is set in the CharacterMovement Component, the distance from the character capsule to the floor increases by one unit while crouching. Regression: No - Same behavior occurs in 4.16.3 ...

Crash attempting to use a struct containing a deleted struct in a blueprint and compiling

UE - Gameplay - Blueprint Compiler - Sep 21, 2017

REGRESSION: No, occurs in 4.17 (doesn't repro in 4.16 because orphaned pins wasn't a feature) Crash occurs when the user attempts to use a struct containing a deleted struct in a blueprint. ...

UMG element clipping does not work on Galaxy S8 (Mali)

UE - Platform - Mobile - Mar 13, 2018

UMG clipping requires stencil. Seems like we don't request stencil when creating backbuffer Changing const int EGLMinStencilBits = 0; to const int EGLMinStencilBits = 8; fixes this. ...

RF_WasLoaded is set to False in PIE for instances of a Blueprint if the Blueprint is recompiled

UE - Gameplay - Blueprint - Apr 5, 2019

The RF_WasLoaded flag is set to false for Blueprint instances in PIE if the Blueprint is edited and compiled. This is fixed by saving the level which is a simple workaround but this should be needed ...

Cannot change Collision Profile of BP component instances

UE - Simulation - Physics - Oct 24, 2019

BP instances placed in level cannot have their components' collision profiles modified to anything other than default and custom. Note that this did not occur in 4.22 (after applying the separate ...

Niagara system loses source emitters when moving Engine from 4.22 or earlier to 4.23 or later.

UE - Niagara - Nov 29, 2019

The following code causes this behavior.// NiagaraSystem.cpp for (FNiagaraEmitterHandle& EmitterHandle : EmitterHandles) { EmitterHandle.ConditionalPostLoad(NiagaraVer); if (!EmitterHandl ...

Problems in skeletal mesh merge

There are a few issues a licensee has found with the skeletal mesh merge operation. See the UDN for more details and the proposed fixes. Note, the issue with the cloth merge is already logged in a ...

bIgnoreAllPressedKeysUntilRelease only applies to keys in the previous mapping

UE - Gameplay - Input - Jun 16, 2022

This is because the RebuildControlMappings function only checks this flag when you have a mapping that was already added, we should apply this for any new mappings as well.  I'll update the repro s ...

Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters

UE - Graphics Features - Nanite - Jan 21, 2025

The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...