Here's how to find your "Google App Authorization" settings - see this article on how applications have a "perpetual, invisible" window into your gmail account.
First,open your Gmail window and click on your name in the upper-right corner to get this drop-down:
Select "Account settings" as shown here. This will open a window like the following:
Select the "Edit" option for the "Authorizing applications & sites" choice as shown above. This will bring up the authorization page showing what applications have been given permission to access your Google account.
Here we see that only the site "code.google.com" - for the "Google Calendar" application - has authorization to access my Gmail account.