Niagara Particles in Mesh Shape Don't Render in Scene or Editor Preview

UE - Niagara - Dec 19, 2019

Niagara particles aren't rendered in the Niagara Editor Preview or the scene when an emitter is in it. Found in 4.24.1 CL#10756747 Reproduced in 4.25 Main CL#10808197 ...

Macro can have Pass-By-Reference type input

UE - Gameplay - Blueprint - Mar 30, 2020

Input arguments of macros are always Pass-by-Reference. So this is just only pin looks matter. Pass-By-Reference modifier on Macro input was removed in 4.24. [Link Removed] ...

Crash saving blueprint with a Get Float Attribute node and the attribute pin is set inline

UE - Foundation - Core - May 5, 2020

REGRESSION: Does not occur in 4.24 Crash occurs when saving a blueprint that is using a Get Float Attribute node and the Attribute pin is set inline. Does not occur if the pin is connected. ...

Duplicating BP actors reset edited Variables to Default Value if Variables name start with Chinese Character

UE - Foundation - Core - Jul 29, 2020

Hints: It has no problem in 4.24, only happening in 4.25 It has no problem as long as the Variable name is contained with Alphabat(English characters) fully; or start with Alphabat(A_变量 is fine) ...

Problems in skeletal mesh merge

UE - Editor - Content Pipeline - Asset Build - May 10, 2021

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 ...

Copy-pasting custom property nodes (ControRig etc.) results in invalid bindings, perf issues

UE - Anim - Rigging - Control Rig - Jul 28, 2025

From this UDN: [Link Removed] Suggested fix:Override PostPasteNode to perform the GUID update andAdd validation on load to strip 'invalid' copies that do not correspond to a valid pin input ...

Crash when changing "MaximumTextureSize" in "LeaveExistingMips" state

UE - Editor - Content Pipeline - Import and Export - Dec 2, 2019

No problem with 4.22.3 ...

Geometry Material Alignment not functioning in 4.8

Tools - Jun 15, 2015

Material Alignment on BSPs are not functioning in 4.8.0 Release. This is a regression from 4.7.6. The issue does appear to be fixed and functional in 4.9 (Promotable-CL-2581018) ...