This extension allows you to create a new presentation and easily navigate through the slides of the deck using the cards and the "back" button. 

When you open the extension, you will be asked to sign in to your Google Account or create a new one. Once you sign in or sign up, you will be able to add content to the new presentation. You will be able to navigate the slides by the "Back" button and the "View" button. You can also open the "Presentation" page to find more information about the extension and the Google Slides application.