Projects that use plugins located outside of either the Engine or Project directories cannot be deployed.

UE - Foundation - Cpp Tools - Plugin System - Dec 5, 2016

Trying to deploy a project that uses an external plugin (not located in either Engine/Plugins or Project/Plugins) will fail. The error message states that it is looking for the plugin to be located ...

UMG widget callbacks do not set PIE context in editor

UE - Editor - UI Systems - May 21, 2018

This is from a UDN post. Several gameplay functions, such as level streaming and SoftObjectPtr resolution, depend on the GPlayInEditorID being set when that code is executed in PIE in the editor. T ...

Anim notify gets skipped when clips are placed next to each other

UE - Anim - Sequencer - Jan 12, 2017

If a sequence has two clips(of a same animation) placed next to each other, some of the anim notifies do not seem to be called. In 4.14, the middle notifies are skipped (e.g. notifyBegin/1st clip ...

The light in the Blueprint Editor's Preview Scene does not respond to any lighting channel but 0.

UE - Framework - Blueprint Editor - Jun 28, 2024

In the Blueprint Editor, Primitive Components can be configured to respond to Lighting Channels 0, 1, and/or 2. However, if channel 0 is disabled (even with another one enabled), the Preview Actor's ...

[CrashReport] UE4Editor_Engine!FSceneView::FSceneView() [sceneview.cpp:627]

UE - Editor - UI Systems - Slate - Apr 11, 2017

Opening UE4.14 using thecommand line "-forceenablecrashtracker," results in a red circle on the top right of the editor that when clicked provides a link to a 20 second video recorded from when you ...

Landscape Splines in Partially Loaded World Partition Levels Can Cause Nanite Landscape Invalidation

UE - Graphics Tools - Terrain - Nov 7, 2025

Certain placements of landscape splines in world partition levels can cause Nanite landscape proxies to invalidate, and switch back to their non-nanite version. This happens when specific regions of ...

IPA Package Sizes have Increased between Versions

UE - Platform - Mobile - Feb 21, 2017

When packaging for iOS the IPA file seems to have increased in size from previous versions. The licensee made an important observation that it appears the master materials have almost halved in si ...

Meshes with scaled root bones pop when entering simulation

UE - Runtime - Simulation - May 15, 2026

This issue is fallout from the changes in 33851494. Prior to that, we didn’t get the pop on beginning the sim. The problem appears to be that in USkeletalMeshComponent::PerformBlendPhysicsBones we ...

Tabbing out of exclusive fullscreen leaves the window & backbuffer in an incorrect state

UE - Editor - UI Systems - Apr 24, 2020

With windows 10 there has come some new swap chains, which unfortunately messes some things with regards to fullscreen up. We've fixed a bunch in the renderer (which would downright cause crashes), ...

Increase in Engine Stats for large amounts of Hierarchical Instanced Static Mesh Components

UE - Graphics Features - Apr 18, 2017

Increase in Engine Stats for large amounts of Hierarchical Instanced Static Mesh Components User Description: We are having performance drops of almost 5ms in 4.15 when using "Hierarchical Instanc ...