If you are a macOS user and are tired of juggling windows and tabs in Safari to go to Youtube, Twitter, Spotify and so on, there is an application that you will love.
It’s called MenubarX and it allows you to add quick access to your favorite services to the menu bar icons. It’s a menu bar browser if you prefer.
In the free version, you can have up to two on hand. Beyond that, you will have to pay a few euros for a lifetime license (which is increasingly rare).
In short, it’s a fairly limited use anyway, but if there are online services on which you spend your life, it can surely save you time.