Steps to reproduce:
1. Create Unity project using Universal 3D Template
2. Install VFX Graph package via Package Manager
3. Install Learning Templates
4. Create “Pivot Advanced” VFX from “Create new VFX Asset” window
5. Open VFX Asset
6. In Toolbar, at the top right, press on a arrow down button
7. In the dropdown menu select “Learning Templates”
8. Once reinstalled, observe the Console window 

Actual results: “NullReferenceException: VFXMemorySerializer::StoreObject failure.
UnityEditor.VFX.VFXMemorySerializer.StoreObjectsToByteArray (UnityEngine.ScriptableObject[] objects, UnityEngine.CompressionLevel compressionLevel) <0x3ba213230 + 0x0005f> in <698bb565b7c648799cf0e90e7a6d53f7>:0” & “Broken text PPtr in file(Assets/Samples/Visual Effect Graph/17.4.0/Learning Templates/VFX/StripSpawnRate.vfx). Local file identifier (8926484042661615218) doesn't exist!
UnityEditor.EditorApplication:Internal_CallUpdateFunctions ()“ errors are thrown in the Console window
Expected results: No errors should be thrown in the Console window

Reproducible with versions: 6000.4.0a4
Not reproducible with versions: 6000.3.0b8, 6000.4.0a3 (different errors)

Tested on (OS): macOS Silicon, Tahoe 26.0 (M1)

Notes:

•  on 6000.3.0b8, 6000.4.0a3 errors thrown: Problem detected while importing the Prefab file: 'Assets/Samples/Visual Effect Graph/17.3.0/Learning Templates/Prefabs/TurntableWithBackdrop_VFX.prefab'.

The file might be corrupt or have a missing Variant parent or nested Prefabs. See details below.
Errors: Prefab Variant problem. Missing Prefab Variant parent: 'TurntableWithBackdrop_VFX (Missing Prefab with guid: 0bc1879d774271a4bab62da6b2f6eac2)'
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)