Unreal Engine Issues
Unreal Engine Issues
OverrideVertexColor causes a crash on mobile renderer
UE - Platform - Mobile - Jan 8, 2026Setting Allow CPU Access on the mesh, or setting bSupportsManualVertexFetch=1 in Engine.ini, avoids the crash. ...
Engine crashes when renaming assets inside an L10N folder.
UE - Editor - UI Systems - Localization - Mar 3, 2026The engine crashes when renaming a localizable asset inside an L10N folder. The engine attempts to associate it with the original localizable asset, but it is unable to find it and ends up accessing ...
UAbilityTask_SpawnActor::BeginSpawningActor may return true when SpawnedActor contains stale value
UE - Foundation - Mar 15, 2026UAbilityTask_SpawnActor::BeginSpawningActor assumes the incoming AActor*& SpawnedActor parameter is nullptr if no actor was spawned, but it does not initialize the parameter at the start of the func ...
Wrong calculation of "MaxAllocatedCountEstimate" inside FNiagaraRendererRibbons::GenerateDynamicData()
UE - Niagara - Mar 20, 2026Starting with UE 5.4, function FNiagaraRendererRibbons::GenerateDynamicData() from file [NiagaraRendererRibbons.cpp] attempts to calculate DynamicData->MaxAllocatedCountEstimate as such: DynamicDat ...
Structure variables in Child Blueprints do not maintain the default values set in their Parent Blueprints
UE - Gameplay - Blueprint - Jan 12, 2015Values changed to an inherited Struct variable in a Child Blueprint will be kept after compile, but any not changed will be set to 0s. ...
After compile, spawnable actor is stuck in spawned state
UE - Anim - Sequencer - Jun 3, 2016After compile, spawnable actor is stuck in spawned state ...
Lock Actor Movement doesn't prohibit rotating an object by turning the viewport while piloting it.
Tools - Jun 12, 2015If you pilot an object and wish for it not be moved, such as a camera, you can use the Lock Actor Movement option. This will stop the object from moving, but it will not stop the object from being r ...
Clicking the [Absolute] bottom of Buttons in Toolbar does not Function
Tools - Sep 9, 2015Hovering over the absolute bottom of buttons in the toolbar, particularly in Blueprints, results in the button being highlighted, but not accessable. The area seems to be 1 or 2 pixels from the bot ...
Performance will drop in PIE if simulate physics is toggled rapidly on an actor with attached components
UE - Gameplay - Nov 3, 2015Performance will drop in PIE if simulate physics is toggled rapidly on an actor with attached components User Description: Simulating physics for Primitive components causes severe performance dr ...
Opening a DataTable that is set to a Struct that is using a Key variable will crash the editor
Tools - Nov 3, 2015Opening a DataTable that is set to a Struct that is using a Key variable will crash the editor User Description: I'm getting this crash when using Key variable in DataTable. I was able to repro i ...