The pin in the Customize Yourself section. It’s in the top corner.
All this does is lock the windows that appear when selecting a sub-section. E.G Shoes. Boots. So, if you click on the pin it moves to a vertical position. That means it’s locked. If your mouse pointer wanders off the window it doesn’t close itself.

To make the window disappear you just click on the pin again so it’s horizontal again and move the mouse pointer off the window and it automatically closes.
It also goes to the unlock option when you click on sex clothing, jewelery, etc.