Unreal Engine Issues
Unreal Engine Issues
Crash occurs when opening a Blueprint that contains a variable that is of a type of a child of the Blueprint, as well as a component containing instanced UObjects
UE - Gameplay - Blueprint - Dec 23, 2016A crash that is possibly the result of a circular dependency can occur if a Blueprint containing an ActorComponent with instanced UObjects and a variable that is a type of a child of itself is opene ...
Always Relevant actor may replicate incorrect movement mode when the walkable floor becomes irrelevant
UE - Gameplay - Player Movement - Feb 26, 2024When the character class is set to always relevant, if a client travels very far away from another character, such that the character is relevant but the component they're standing on is not (but al ...
FBlackboardKeySelector filters aren't applied when recompiling blueprint if a behavior tree asset containing the blueprint added as a service is closed, or if the blueprint is reparented.
UE - AI - BehaviorTree - Sep 24, 2025Context In Behavior Trees, BT Services can be added to nodes. Those services can have configurable FBlackboardKeySelectors. BlackboardKeys are variables on a blackboard that the behavior tree can r ...
Renaming a Blackboard Key removes it's references in the Behavior Tree
UE - AI - Jan 27, 2015Renaming a Blackboard Key removes it's references in the Behavior Tree ...
Parent component visibility in a child blueprint isn't reflected in a launched project.
UE - Gameplay - Blueprint - Mar 5, 2015Parent component visibility in a child blueprint isn't reflected in a launched/packaged project. ...
After breaking a level instance without Actor Folders, moving its actors between folders of the world-partition map does not work correctly
UE - World Creation - Worldbuilding Tools - World Partition - Jan 29, 2024If a standard level (without Actor Folders enabled) is added to a world-partition map (with Actor Folders enabled) as a Level Instance, and then that instance is "broken" so that its actors are inco ...
Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage
UE - Niagara - Feb 28, 2025Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...
Gameplay Tags with the string "None" as any of its hierarchical node identifiers behave incorrectly (because of an incomplete generated FGameplayTagContainer::ParentTags array)
UE - Gameplay - Nov 19, 2024Currently, using the string "None" as a hierarchical node identifier inside a Gameplay Tag (for example "A.B.C.None.D.E.F") is not disallowed by the engine, but results in some incorrect behaviors. ...
Physics Constraints do not have the same values if they are part of an 'Always Loaded' level
UE - Gameplay - Dec 3, 2014Physics Constraints do not have the same values if they are part of an 'Always Loaded' level. They will work correctly in the Persistent level and a level that is Streamed in. This becomes problem ...
Collision of child actor doesn't rotate if the parent is simulating physics
UE - Simulation - Physics - Aug 11, 2015Collision of child actor doesn't rotate if the parent is simulating physics. This was an old bug that an AnswerHub user reported back in 4.9 but now a licensee is reporting this same behavior in 4.1 ...