During blueprint reparenting SimpleConstructionScript subobject unmodified values are retained as modified values

UE - Framework - Blueprint Editor - Nov 27, 2024

When reparenting blueprints and both the old and new parent blueprint contain a subobject but with different values on it, the reparented blueprint doesn't correctly inherit values from the new pare ...

Input Actions bound to Any Key become unresponsive after mouse scroll until scrolled again

UE - Gameplay - Input - Mar 28, 2025

In UE latest release (5.5 launcher version), Enhanced Input Actions mapped to "Any Key" stop responding after scrolling the mouse wheel. Specifically, scrolling either up or down disables the Any Ke ...

Water is missing or appears in wrong places due to incorrectly rendered WaterInfoTexture.

UE - Graphics Tools - Terrain - Water - Jun 16, 2025

Water is missing, appears in strange blocks, or appears in wrong places due to incorrectly rendered WaterInfoTexture. The WaterInfoTexture is part of the WaterZone actor. ...

Actor attached to child actor fails to serialize as part of map

UE - Framework - Components - Nov 3, 2023

Attaching other actors to a child actor (actor spawned by ChildActorComponent) fails to serialize correctly as part of the map. The attached actor loads as detached and resets its position back to w ...

UV Offset Effect Material in RetainerBox Causes Visual Artifacts in Editor Preview

UE - Editor - UI Systems - UMG - Apr 22, 2025

When a UV Offset is applied in a RetainerBox effect material, visual artifacts appear only in the editor — not at runtime — if a widget with a dotted preview outline (like CanvasPanel) is placed dir ...

Editor vs Runtime: Inconsistent data layer behavior when attaching actors

UE - World Creation - Worldbuilding Tools - World Partition - Jun 5, 2025

In editor, data layer system respects the data layer settings for each actor, but at runtime, the condition check is made collectively for each actor cluster, resulting in differences in behavior. ...

Stale VSM pages after HLOD transition

UE - Graphics Features - Shadows - May 23, 2024

Virtual Shadow Maps do not invalidate pages when HLODs replace meshes. This can lead to inconsistencies between the geometry and the shadows, which can cause artifacts as pages are invalidated. ...

Placed level instance causes "!ActorInstanceGuid.IsValid()" assertion after changing WorldSettingsClass

UE - World Creation - Worldbuilding Tools - Level Instances - Nov 13, 2023

Resaving the level using ResavePackagesCommandlet is a workaround. ...

World Position is incorrect when used to control the opacity mask in a nanite spline mesh

UE - Graphics Features - Feb 20, 2025

When calculating the opacity mask, Nanite spline meshes do not have the correct World Position in the Material. This leads to visual artifacts when the mask relies on the world position. ...

Masked material using virtual textures covering a decal will result in black pixels

UE - Graphics Features - Nanite - Mar 31, 2025

Depth Passes for Masked Materials using Virtual Textures does not work correctly when it is in front of a Nanite Mesh and a Decal, resulting in black artifacts. Also tested on //UE5/Main, CL: 41024 ...