Steps to reproduce:
1. Open the attached project “VFXGraphIssue“
2. Import the attached VFX graph “VFXBug“
3. Open the imported VFX graph
4. Observe the Console window

Expected result: VFX graph is opened without any errors
Actual result: VFX graph fails to open with console errors

Reproducible with: 2021.3.14f1, 2021.3.17f1
Not reproducible with: 2020.3.43f1, 2021.3.13f1, 2022.2.5f1, 2023.1.0b2, 2023.2.0a1

Reproducible on: Windows 10

Console errors:
1. Exception thrown while invoking [OnOpenAssetAttribute] method 'VisualEffectAssetEditor:OnOpenVFX (int,int)' : NullReferenceException: Object reference not set to an instance of an object
2. NullReferenceException: Object reference not set to an instance of an object
UnityEditor.VFX.UI.Vector2PropertyRM.UpdateIndeterminate () (at Library/PackageCache/com.unity.visualeffectgraph@12.1.8/Editor/GraphView/Views/Properties/Vector2PropertyRM.cs:71)