Steps to reproduce:
1. Create a new project
2. Add a new script which has a public field surrounded with a "#if UNITY_EDITOR" pre-processor check
3. Place it on the Main Camera in the scene
4. Build and run the project with the current scene
5. See this error in player log:
"A script behaviour has a different serialization layout when loading. (Read 24 bytes but expected 28 bytes)
Did you #ifdef UNITY_EDITOR a section of your serialized properties in any of your scripts?"