To reproduce:
1. Create a new project
2. Create a script
3. In the script create a public variable
4. Attach the script to a gameobject
5. Select the gameobject
6. Switch the inspector to debug mode
7. Comment out the public variable from the script
8. Switch back to Unity
Expected result: The variable disappears
Actual result: The whole inspector get's garbled
Note: Watch screencast for repro video