Preferences window opens at every restart

### Bug

The preferences window opens every time I restart. This is a bit annoying because it can’t be turned off if the program is scheduled to run automatically when I log in.

### Steps to reproduce

1. Open the preferences window
2. Ceck `Start Hidden Bar when I log in`
3. Restart your computer
4. See error: The preferences window opens

### Expected behaviour

The window should only open when I click the app icon or open the preferences from the menu bar.

### Environment

**Desktop:**
- OS: macOS Big Sur
- Version: 11.4