It's a browser extension that doesn't require any add-ons or permissions. You don't have to install any software to use it.

To make it work, you need to have Google Chrome installed. You can also use it with any other browser, but Google Chrome is recommended.

You'll need to enable Gmail in the settings.

To use this extension, open the main view of your Gmail account.

When you enable the extension, it will hide the inboxes when you open the app.

Then, it's up to you. You can view the inboxes anytime you want. To view all of your emails, just click the button.

The buttons in the top right of the window let you switch between showing and hiding your emails.