Navmesh doesn't work in a Packaged Build if it was placed in a Sublevel

UE - AI - Oct 19, 2018

Once packaged, a persistent level is unable to create navmesh data properly if the navmesh bounds volumes are only present in its sublevels. The issue can be traced to the UNavigationSystemV1::IsThe ...

Trying to chord two buttons already mapped to actions to fire a third action when both are actuated fails.

UE - Gameplay - Input - Apr 14, 2022

We're aiming to set up LT - action 1, RT - action 2, LT + RT - action 3 here. I don't think this is supported via chording at present. You'd need to handle it manually (probably via adding/removing ...

AbilitySystemComponent::NotifyAbilityEnded Can Crash due to Callbacks Invalidation Specs

UE - Gameplay - Gameplay Ability System - Oct 11, 2023

Pasting from the UDN: Unsafe code in AbilitySystem can lead to crash when granting an ability inside OnAbilityEnded Hello. We just ran into a crash. After investigation, it seems to be caused by ...

Stale VSM pages after HLOD transition

UE - Rendering - 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. ...

Crash when saving after resetting Instanced array element via Property Matrix on placed actors

UE - Editor - Nov 21, 2025

When an Actor Component contains an Instanced UObject array marked EditDefaultsOnly, adding a new element to the Blueprint defaults correctly updates the Blueprint and its own Property Matrix. Howev ...

Math Expression Node produces error if it calls a variable located within a hidden variable category

UE - Gameplay - Blueprint - Jan 29, 2016

The math expression node in blueprints does not recognize variables that have been hidden within a blueprint category. ...

LIVE: Reflection Capture are not working with moveable directional light on mobile

UE - Graphics Features - Nov 3, 2014

When a Directional Light is changed from static to movable, the materials in the level will appear dark. ...

Landscape incorrectly renders when camera clips through foliage while Playing in Editor

UE - LD & Modeling - Terrain - Landscape - Dec 1, 2014

Landscape sections disappear for a very brief time when the player camera clips through foliage quickly. ...

Timeline functions do not work inside of Blueprint functions

UE - Gameplay - Blueprint - Dec 20, 2014

I could not repro their issue in main. They supposedly recently upgraded to 4.5. I was wondering if you could divide an conquer, and figure out when we fixed this. **EDIT** Was able to repro in mai ...

'Set Playback Position' node fires Timeline event even if 'Fire Events' is set to false

UE - Gameplay - Apr 30, 2015

'Set Playback Position' node fires Timeline event even if 'Fire Events' is set to false. User Description: Basically using the set playback position node to set a new time position for a timeline ...