AI Perception UnregisterSource Sense == nullptr does not affect pending adds

UE - AI - Perception - Jun 15, 2022

UAIPerceptionSystem::UnregisterSource according to its documentation should treat Sense == null as targeting all sources, but the code for removing pending sources does not treat Sense == null as th ...

Hide Categories in a blueprint will not affect categories in inline components

UE - Editor - Workflow Systems - Oct 12, 2022

This occurs because ObjectPropertyNode.h will only check if a category is hidden for it and its subclasses. It should also be checking the parent's categories if it's an edit inline component. ...

WP level instance runtime settings affect streaming generation

UE - World Creation - Worldbuilding Tools - World Partition - Nov 16, 2023

If a level instance uses different runtime settings then it can override the main WP's runtime settings with UWorldPartitionRuntimeSpatialHash::ApplyCVars Runtime settings:GRuntimeSpatialHashUseA ...

Level Streaming - Always Loaded sublevel affected by streaming volumes

UE - World Creation - Worldbuilding Tools - Mar 19, 2024

The docs mention: "When a streaming Level is set to Always Loaded, it is loaded together with the persistent Level. It also becomes visible at the same time as the persistent Level. It ignores strea ...

Branching Points in a Montage Affect the Rotation Outcome of Root Motion

UE - Anim - Runtime - Mar 28, 2025

When playing Montages with Root Motion, the sub stepper extracts root motion transform in small increments. If a Branching Point exists within the interval being extracted, the extraction range is s ...

SetGamePause does not affect Sequencer pause if using audio clock as source

UE - Audio - Sequencer - Oct 24, 2025

We’ve run into some unexpected behavior when combining SetGamePause(true) with Level Sequences. When calling SetGamePause(true) while a Level Sequence is playing, the visuals pause correctly, b ...

Having a block in layout before switching to overlay strategy affects the overlay output.

UE - Anim - Mutable - Mar 5, 2026

Issue: If "Resizable" Layout Strategy contains a block, it will influence the "Overlay" Layout Strategy. Expected behavior: When using "Overlay" Layout Strategy, it should disregard whatever the "R ...

[CrashReport] Commandlet crash - UE4Editor_Engine!FAnimationUtils::CompressAnimSequenceExplicit() [animationutils.cpp:621]

OLD - Anim - Sep 7, 2017

This is an infrequent commandlet crash that has affected a number of users exclusively in 4.17.1 (possible regression from 4.17.0?). There are also two instances of older cases in 4.13 and 4.15, bu ...

[CrashReport] UE4Editor_CoreUObject!FCompressedChunk::FCompressedChunk()

UE - Foundation - Core - Jul 24, 2017

This is a common crash affecting users in 4.16 and the 4.17 Previews. The two descriptions provided by users say their crash occurred after updating their project from 4.13. User DescriptionsUpgra ...

Wind affects cloth in scene when there is no Wind Directional Source actor placed

UE - Simulation - Physics - Character - Jun 22, 2015

If a character with a cloth simulation or a mesh with a cloth simulation is in the scene there is wind force that is being applied to the cloth. The only way to remove this is by setting a Wind Dire ...