GemHunterMatch3 sample logs "VFXMemorySerializer::StoreObject failure" errors on first import

Steps to reproduce:

1. Clone the UGS Use Case Samples repository, so the GemHunterMatch3 project has no Library folder.
2. Open GemHunterMatch3 in Unity 6000.3.14f1.
3. When the import finishes, look at the Console.

Actual results: The Console shows red errors before you press Play: three NullReferenceException: VFXMemorySerializer::StoreObject failure. errors, one each while importing VFX_Loose.vfx, VFX_Coin.vfx and VFX_Win.vfx. They come after 22 Broken text PPtr messages from those files and 2 more from Controller_PSD_character_mermaid.controller:

Broken text PPtr in file(Assets/GemHunterMatch/VFX/GoalsEffects/VFX_Loose.vfx). Local file identifier (8926484042661615642) doesn't exist!
NullReferenceException: VFXMemorySerializer::StoreObject failure.
  at UnityEditor.VFX.VFXMemorySerializer.StoreObjectsToByteArray (...)
  at UnityEditor.VFX.VFXGraphPreprocessor.OnCompileResource (...) in ...\com.unity.visualeffectgraph@9ffede663017\Editor\Models\VFXGraph.cs:135

Expected results: The sample imports with no errors in the Console.

Reproducible with versions: 6000.3.14f1

Not reproducible with versions: —

Can’t test with versions: —

Tested on (OS): Windows 11 (Editor)

Notes:

• The errors appear only on the first import into an empty Library. They can be cleared, and Play mode still works.
• Cause: the four assets reference sub-objects that don't exist in the files. For example, VFX_Loose.vfx references 8926484042661615642, and that ID isn't defined anywhere in the file.
• Fix in the sample: remove the dangling references from VFX_Win.vfx, VFX_Loose.vfx, VFX_Coin.vfx and Controller_PSD_character_mermaid.controller. Then open the project with an empty Library and confirm the import logs no errors.
• The mermaid controller is the asset from [Internal link], which was closed with a note that it would be fixed in the sample.