Crash upon diffing Blueprint that was reparented when its previous parent has already been deleted

UE - Gameplay - Blueprint Editor - Sep 20, 2017

When attempting to diff a Blueprint that has been reparented when the previous parent no longer exists in the editor, a crash occurs. The crash is due to the editor attempting to reference the delet ...

Sequencer Crash when Hovering over Binding Properties on a Component with Spaces in its Name

UE - Anim - Sequencer - Nov 7, 2025

Crash when binding to new components that have spaces in their name and you attempt to access their bindings. ...

Editor Crashes when working in QAGame TM-Sequencer_EventTrack - TCString<TCharType>::Strlen(InName)

UE - Anim - Sequencer - Jul 12, 2017

Editor Crashes when working in QAGame TM-Sequencer_EventTrack - TCString<TCharType>::Strlen(InName) This Assert happens randomly throughout the repro-steps. I am unsure what about the process cause ...

[AI] BehaviorTreeEditor crash when swapping from Behavior Tree to Blackboard view.

UE - AI - BehaviorTree - Aug 24, 2023

The first time that a Behavior Tree editor window changes from the tree to the Blackboard can cause a crash if you add and remove a key from the Blackboard via a different Behavior Tree editor windo ...

Nullptr Ensure and crash after HotReloading

UE - Foundation - Core - Jan 26, 2017

Following my repro, I hit an ensure and crash. The two times I tried to repro after my first crash resulted in different call stacks. I'll comment the other Jiras once I have them in. One of my cra ...

GAS: FActiveGameplayCueContainer::RemoveCue crash while iterating removals when consecutive Cue tags are conditionally added and the conditional effects removed in ascending order

UE - Gameplay - Gameplay Ability System - Nov 4, 2025

When removing gameplay effects by tag, if the tag that is being removed has other tags that are dependent on it in a cyclical way an "array out of bounds ' error can be triggered. ...

Crash creating local variable in ABP function

OLD - Anim - Dec 5, 2019

Creating a local variable in an ABP function crashes ...

Crashes when attempting to use an Instanced Struct inside Control Rig / Rig VM

UE - Anim - Rigging - Control Rig - Mar 17, 2025

Currently, the Control Rig Editor allows the user to use the "Instanced Struct" type, for example for a variable or function input/output. However, this type does not seem to be properly supported ( ...

Blueprint Editor: BP functions display dropdown instead of checkboxes for uint8 enum parameters

UE - Gameplay - Blueprint Editor - Aug 8, 2017

I traced through the callstack and it looks like the problem is as follows:in order for the BP function to compile, its enum parameter must be uint8, because that is the only type supported by BP fu ...

Assertion occurs when undoing a Child State's unparenting from another Child State in AI State Trees, leading to a crash.

UE - AI - StateTree - Apr 15, 2022

Assertion occurs when undoing a Child State's unparenting from another Child State. Repro Rate: 5/5Assertion failed: false [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Public\Widgets\Views ...