The Left Mouse Button Pressed event is not firing when Input Mode Game Only is set and Show Mouse Cursor is true

UE - Editor - UI Systems - Slate - Sep 20, 2019

The Left Mouse Button Pressed event is not firing when Input Mode Game Only is set and Show Mouse Cursor is true. Attached is an example project (4.23) that demonstrates the issue. Found in 4.23.0 ...

Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling

UE - Graphics Features - Jan 12, 2026

At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...

Play Media Player Node Causes Blueprint Functions to be Uncallable

UE - Gameplay - Blueprint - Feb 23, 2016

This only occurs in standalone or a packaged game Having a Play Media Player node in a blueprint causes all of that blueprint's functions to become uncallable. Found in 4.11 Preview 5. Reproduced ...

Blueprint with instance static mesh from construction script will cause crash when using the build then build geometry

Tools - Mar 12, 2015

When using a BP with component instance static mesh that is added via the construction script, when using the build button in the toolbar to build lighitng and geometry everything will work correctl ...

Painted foliage in a level instance can be selected in Foliage mode if the level instance is in main level, and foliage is duplicated if moved.

UE - World Creation - Worldbuilding Tools - Foliage - Sep 16, 2025

Context Foliage Mode is a set of tools that enables you to quickly paint or erase sets of Static Meshes or Actor Foliage. Level Instancing is a level-based workflow designed to improve and streamlin ...

Unable to save project due to user created blueprint node that creates user created object

UE - Gameplay - Blueprint - Apr 28, 2015

When a user creates a blueprint node of their own that is used to spawn a user created object, the project becomes unable to be saved after the blueprint is put into use. ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

NPC - Does not get updates from Material Parameter Collection changes in the editor

UE - Niagara - Sep 30, 2024

When an MPC is selected as the Source Material Collection for an NPC, all of its current parameters are carried over to the NPC with their current values. After that, if parameters are added to, rem ...

Blueprint derived from C++ class not saving correctly

UE - Gameplay - Blueprint - Jul 27, 2015

The blueprint that the user is using loses some data when the editor closes and reopens despite saving all of the content. Note: Currently unsure of what exactly causes this but as I am able to rep ...

Hidden enumerator variables can cause the enumerator to become broken with the Select node in blueprints

UE - Gameplay - Blueprint - May 26, 2015

If a user makes an enumerator in C++ and sets one of the variables to Hidden and doesn't make it the last variable of the enum, it will cause issues with the numbering of the enum when using the Sel ...