Unreal Engine Issues
Unreal Engine Issues
Cursor locks to ScrollBox in native fullscreen mode are locked in the wrong position
UE - Editor - UI Systems - UMG - Sep 17, 2024When specifying a widget of a different size than the screen in FReply::LockMouseToWidget, the cursor is locked to a different position in native full screen mode. It appears that the window size n ...
Damping is handled differently at lower frame rates
UE - Gameplay - Aug 3, 2016Damping is handled differently at lower frame rates. Slight changes in damping at lower FPS (25) drastically effects objects and isn't applied in the same way as at higher FPS (60) User Description ...
Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak
UE - Framework - Blueprint - Apr 15, 2025When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...
[AI] Debug Render Scene Proxy hits ensure for registering a delegate twice during level streaming.
UE - AI - Debugging - Aug 31, 2022Description from licensee: We're seeing an ensure get tripped up in FDebugRenderSceneProxy that says "DrawDelegate is already Registered!". Debugging the issue, we have confirmed that the DrawDeleg ...
Merging Splines causes Engine to Crash in 5.1
UE - World Creation - Worldbuilding Tools - Merge Actor - Dec 15, 2022Attempting to merge two spline actors causes the Engine to crash. This issue occurs with the Steps to Reproduce regardless if there are more branches added to the tree branch spline/enabled, and reg ...
Interchange framework is bypassed on the second attempt after a failed import
UE - Editor - Content Pipeline - Import and Export - Jul 14, 2025Hello! We have encountered a bug with the Interchange pipeline. When an interchange texture import is cancelled due to non-power of 2, and then the same texture is imported again without any change ...
Chaos : Rigid body sleeps when very small external force is applied by AddForce
UE - Runtime - Simulation - May 25, 2022When a small external force is applied to the rigid body, the VSmooth value is reset in the ResetVSmoothFromForces function. Since this function ignores the current velocity, a very small velocity ...
Pressing the "Show Inactive" button in the material instance editor did not display groups that did not contain the active parameter
UE - Rendering - Architecture - Materials - Aug 1, 2024When pressing the "Show Inactive" button in the material instance editor, all material parameters are supposed to be displayed in the EditorUI. This is not the case, only some of the parameters are ...
Asset returns after being deleted from the content folder while the editor is open
UE - Editor - Content Pipeline - Content Browser - May 8, 2017Asset returns after being deleted from the content folder while the editor is open. A deleted asset comes back and does not prompt to save it. This leads to the asset being removed when the editor i ...
[CrashReport] Assertion failed: !PinRef->bWasTrashed | UEdGraphPin::SerializePin()
UE - Gameplay - Blueprint - Aug 29, 2017This is a common and longstanding crash that has occurred since at least 4.15 and affected nearly 500 users. The CrashGroup was previously linked to [Link Removed], but that had specific repro step ...