Repro steps:

1. Open SampleScene from the attached project.
2. Preview the particle system in the scene view and observe the particles spawning from the sphere
3. Enter play mode
4. Observe the sphere is no longer assigned as it was statically batched.

Notes:
- Requested by user: https://feedback.unity3d.com/suggestions/cache-a-copy-of-a-mesh-for-particle-mesh-emitter
- Potential fix is to cache the mesh vertices
- Not a regression