Firefox has the function of deleting cookies when closing the browser. It also has exceptions to not delete cookies from frequently visited websites. Today, to add exceptions, you have to go to the settings every time, which is quite annoying. My proposal is to add a button that will add or remove the website on which the current user is to the exceptions. The button could be where the extension icons are and the icon would display whether the web page is in exception or not. Extensions work the same way, but the function in firefox works better and always deletes all cookies.