If a website requires a secure connection that cannot be established, Firefox will not connect and will show you an error page. Learn more.
The Firefox "Page Info" window gives you details about the page you're on. You can also use it to change permissions for the website.
Firefox automatically updates itself by default but you can always do a manual update. Learn how to update Firefox on Windows, Mac or Linux.
The Options/Preferences panels give you access to Firefox settings. This article describes what types of settings are available in each panel.