Application.loadedLevelName doesn't report the correct level name in the editor unless the scene has been played at least once since loading.

- Import the Unity Package.
- Load the scene 'LevelNameTest'
- Select the GameObject in the scene named GameObject.
- Click the "Print Loaded Level Name" button in the custom inspector.
- Check the debug log, it shows that the current value for Application.loadedLevelName is "".
- Press Play to run the scene, then again to stop the scene.
- Press the button "Print Loaded Level Name" in the inspector again. The Debug log should now display the correct name for the level.