1. Click on the "Theme" tab in the sidebar editor.
2. Click on "Table of Contents" to expand option preferences.
3. In the dropdown menu under "Keep", here is where you can select to have the menu remain open or closed.
4. To preview this, click on the top left corner button and hit "Preview" to check the update.
5. In this example, you will see that this Table of Contents menu remains open.
