Level cannot save when compile setting is changed on blueprint present in level

UE - Gameplay - Blueprint - Aug 21, 2017

When using a project that has a blueprint in a level when the project is created, there is an issue that is occurring when you modify the compile settings and attempt to save the level There is an e ...

Interpolators of Particle Dynamic Parameters Need "nointerpolation".

UE - Niagara - Aug 1, 2019

Regardless Niagara or Cascade, dynamic parameters for particles are passed to pixel shaders from vertex shaders via InterpolantsVSToPS. It can cause a precision error on some materials, for example ...

RVT output from Landscape Height gets incorrect mip cache loaded

UE - Rendering - Architecture - Oct 13, 2021

I test it for more information for your reference:It happens only when a Landscape *Height *was output to the RVT, other Landscape's maps like BaseColor are all fine, as well as Height output from o ...

GameplayTagQuery AutoDescription not refreshed after GameplayTag redirect on load

UE - Gameplay - Gameplay Tags - Jan 21, 2026

FGameplayTagQuery does not refresh its cached AutoDescription after GameplayTag redirects are applied during asset load. As a result, after renaming a GameplayTag and restarting the editor, the Game ...

Light as If Static setting does not Persist when Re-opening Project

Tools - Apr 28, 2016

This bug was originally entered back in 4.8 as [Link Removed], but was closed as by design. The reason was, the mesh did not have Lightmap UVs, so using the 'Light as If Static' option would not wor ...

[CrashReport] Crash in PHAT on LeftMouse click while moving ragdoll asset during Simulate

UE - Simulation - Physics - Oct 25, 2017

Crash occurs in the updated Physics Asset Editor if you LeftClick while moving a ragdolled asset during Simulation. This is a regression from 4.17.2 User Descriptionsin the new physics asset edit ...

Comment Box Edges/Corners Do Not Precisely Follow Cursor when Resizing

UE - Editor - UI Systems - Slate - Oct 10, 2017

When resizing comment boxes, the edges/corners do not follow the cursor precisely, especially when the cursor is moved around quickly. On Windows, the cursor will either get ahead of the box or ins ...

HLODs appear dark/near black when built for very large geometry with Virtual Textures enabled

UE - World Creation - Worldbuilding Tools - HLOD - Jan 27, 2025

Building HLODs for a very large landscape with Virtual Textures enabled results in the built HLODs being very dark for the most part. Building the same large landscape's HLODs with Virtual Textures ...

Missing PSO Precaches in the engine

UE - Rendering - Architecture - RHI - Aug 20, 2025

A licensee wanted to report some missing PSO Precaching they found, which they have fixed locally: 1. UCableComponent doesn't implement CollectPSOPrecacheData or call CheckPSOPrecachingAndBoostPri ...

Crash When Loading Cooked Material Assets in Editor Due to Shader Serialization

UE - Rendering - Architecture - Shaders - Aug 27, 2025

In Unreal Engine 5.6+, the new shader serialization logic in FShaderMapResourceCode::Serialize does not correctly handle cooked assets that are loaded back into the editor (e.g., from a mounted .pak ...