The "address bar" is a small space in a web browser where you can type in the website's name or address. It helps you navigate to a specific webpage or website on the internet. Full definition
If all you want to do is remove the button, it's easy: just right - click on the button and choose «Remove from Address Bar». (howtogeek.com)
The layout is desktop - like with the tabs and address bar on top. (the-ebook-reader.com)
Additionally, you will see a closed lock somewhere on your browser address bar (each browser shows it in a slightly different way). (nationstrafficschool.com)