Non-nativized classes that implement a nativized interface class do not get interface methods called when invoked through a Blueprint function library.

UE - Gameplay - Blueprint - Jul 5, 2018

UObjectBaseUtility::GetInterfaceAddress() fails due to an incorrect serialized value of the 'bImplementedByK2' property within the non-nativized class's Interfaces array on save. See support thread ...

HLOD visibility state isn't cleared when changing scene

UE - Graphics Features - Sep 25, 2018

HLOD state is not cleared when moving to a scene without HLOD so primitives may read the state from the old scene and incorrectly cull objects. The safe fix is to clear the HLOD state maps when the ...

Setting a Vector value in the Material Parameter Collection causes crash

UE - Graphics Features - Mar 1, 2019

Creating a Vector parameter within the Material Parameter collection causes a crash with the engine. Tested in 4.21.2 (CL - 4753647), 4.22 (CL - 5159901), 4.23 (CL - 4980862) ...

Crash on debugging a minimized Blueprint (access violation in SWatchTreeWidgetItem)

UE - Gameplay - Blueprint Editor - Mar 27, 2019

Debugging a blueprint with a breakpoint while the Blueprint Editor window is minimized causes the editor to crash. Tested in 4.21.2 (CL - 4753647), 4.22 (CL - 5531554), 4.23 (CL - 5586947) ...

Shadows are Heavily Aliased with PCSS Enabled

UE - Graphics Features - Apr 11, 2019

Shadows are exetremely rough and aliased if r.shadow.FilterMethod is set to 1.  Working as expected in 4.21 CL# 4753647  Found in 4.22 CL# 5660361 and 4.23 CL# 5810496 ...

Editor Crash While Using "Snap to Floor" Shortcut on Some Foliage Instance.

UE - World Creation - Worldbuilding Tools - Foliage - Apr 15, 2019

When pressing the End key to have a foliage mesh "snap to floor/surface" the editor will crash. Found in 4.21 CL# 4753647, 4.22 CL# 5660361, and 4.23 CL# 5898046 ...

Camera FOV Above 90 Causes Landscape LODs to Flicker

UE - LD & Modeling - Terrain - Landscape - Apr 17, 2019

Camera FOV Above 90 Causes Landscape LODs to Flicker Found in 4.20 CL# 4369336, 4.21 CL# 4753647, 4.22 CL# 5660361, 4.23 CL# 5934407 ...

Adding an LOD while in PIE or Simulate Cauases the Editor to Crash

UE - Niagara - Apr 29, 2019

If you add an LOD while the editor is simulating or playing, the Editor Crashes. Found in 4.20 CL# 4369336, 4.21 CL# 4753647, 4.22 CL# 5660361, 4.23 CL# 6063286 ...

Flickering / Color Shift in Right eye with Cascade Particle + Instanced Stereo

UE - Niagara - May 13, 2019

Flickering or shifted color will be seen in the Right Eye. User reports that moving the nodes from the material function to the base graph resolves the issue. Confirmed in 4.23 MAIN branch @ CL 6 ...

Selected Objects Turn Pink in Lightmap Density View Mode

UE - Graphics Features - May 17, 2019

Selected Objects Turn Pink in Lightmap Density View Mode. Works as expected in 4.21 CL# 4753647 Found in 4.22 CL# 6063286 and 4.23 CL# 6395561 This is a regression. ...