Unreal Engine Issues
Unreal Engine Issues
Ensure when calling server RPC from BeginPlay for a component that is not replicated by default
UE - Networking - Sep 18, 2025This seems to occur due to the order in which the component is registered and set to replicate in UActorComponent::OnCreatedFromReplication. The component is first registered with the world, which c ...
Mover character stuck continuously correcting movement after having a skeletal mesh as movement base
UE - Gameplay - Player Movement - Mover - Sep 8, 2025Once a mover character has had a skeletal mesh set as its movement base, it appears to get stuck in a desynced state after moving to a static movement base. It is only when the character's movement ...
Invalid GUIDs on new material instance parameters cause overrides to break on base param rename
UE - Rendering - Architecture - Materials - Sep 3, 2025When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...
Negatively scaled box collisions render back faces in Player Collision debug view
UE - Simulation - Visual - Sep 1, 2025The player collision debug visualization for negatively scaled boxes is rendering the back faces, not the front faces. The debug primitives are rendered via the dynamic mesh builder. FDynamicMeshBui ...
UMG Retainer Box renders incorrect colors with Color Vision Deficiency enabled
UE - Editor - UI Systems - UMG - Aug 27, 2025When using a Retainer Box in UMG with Color Vision Deficiency enabled, the content inside the Retainer Box is rendered with incorrect colors compared to the rest of the UI. This bug is present in UE ...
Heterogeneous Volume Actor causes ensures to trigger in Debug builds
UE - Niagara - Aug 24, 2025When a heterogeneous volume actor is used with a volume material in a debug build, the following ensures are triggered: Ensure condition failed: UniformBufferValue || EnumHasAnyFlags(AutomaticallyBo ...
Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected
UE - Rendering - Architecture - Materials - Aug 24, 2025Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected. The licensee noticed this in a ...
Niagara Data Interface "Errors and Warning" section on Module Details not updating when error messages change
UE - Niagara - Aug 14, 2025This is a regression: it worked correctly up to UE 5.5, but not in 5.6 or mainline latest. Possibly caused by CL 40093049. Class UNiagaraDataInterface provides virtual method GetFeedback(), which a ...
ULevelInstanceSubsystem::CreateLevelInstanceFrom() is not honoring parameters bAlwaysShowDialog and LevelPackageName
UE - World Creation - Worldbuilding Tools - Level Instances - Aug 6, 2025A Level Instance or Packed Level Actor can be created through editor scripting by using function ULevelInstanceSubsystem::CreateLevelInstanceFrom(), which receives parameters packed in the FNewLevel ...
Environment Query System (EQS): EnvQuery runtime template object can be created with a non-unique name, corrupting the EnvQueryManager cache
UE - AI - Aug 5, 2025On file [Engine\Source\Runtime\AIModule\Private\EnvironmentQuery\EnvQueryManager.cpp:812], function UEnvQueryManager::CreateQueryInstance() uses StaticDuplicateObject() to create a new UEnvQuery* (d ...