Steps to reproduce:

1. Open attached project
2. Open TestGraph VFX asset
3. Start linking TestFloat Property and/or Add nodes
4. Hover over or near the Anchor before releasing the mouse button

Actual results: NullReferenceException: Object reference not set to an instance of an object is thrown

Expected results: No errors or warnings are thrown when connecting Edges

Reproducible with versions: 2022.3.56f1, 6000.0.34f1, 6000.1.0b2

Tested on (OS): Ubuntu 24, macOS 15.2

Notes:

• Couldn't reproduce in ShaderGraph. Tested using the same setup (1 Float Property and Multiple Add blocks)

Full error message:

• NullReferenceException: Object reference not set to an instance of an object

UnityEditor.VFX.VFXSlot.CanLink (UnityEditor.VFX.VFXSlot other) (at ./Library/PackageCache/com.unity.visualeffectgraph@593f22d24cce/Editor/Models/Slots/VFXSlot.cs:795)
UnityEditor.VFX.UI.VFXEdgeDragInfo.DisplayEdgeDragInfo (UnityEditor.VFX.UI.VFXDataAnchor draggedAnchor, UnityEditor.VFX.UI.VFXDataAnchor overAnchor) (at ./Library/PackageCache/com.unity.visualeffectgraph@593f22d24cce/Editor/GraphView/Elements/VFXEdgeDragInfo.cs:63)
UnityEditor.VFX.UI.VFXEdgeDragInfo+<>c__DisplayClass6_0.<StartEdgeDragInfo>b__0 (UnityEngine.UIElements.TimerState t) (at ./Library/PackageCache/com.unity.visualeffectgraph@593f22d24cce/Editor/GraphView/Elements/VFXEdgeDragInfo.cs:124)
UnityEngine.UIElements.VisualElement+TimerStateScheduledItem.PerformTimerUpdate (UnityEngine.UIElements.TimerState state) (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/VisualElementScheduler.cs:361)
UnityEngine.UIElements.TimerEventScheduler.UpdateScheduledEvents () (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/Scheduler.cs:376)
UnityEngine.UIElements.Panel.TickSchedulingUpdaters () (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/Panel.cs:1336)
UnityEngine.UIElements.UIElementsUtility.UnityEngine.UIElements.IUIElementsUtility.UpdateSchedulers () (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/UIElementsUtility.cs:277)
UnityEngine.UIElements.UIEventRegistration.UpdateSchedulers () (at /Users/bokken/build/output/unity/unity/Modules/UIElements/Core/UIElementsUtility.cs:108)
UnityEditor.RetainedMode.UpdateSchedulers () (at /Users/bokken/build/output/unity/unity/Modules/UIElementsEditor/RetainedMode.cs:47)