[Mantine UI Series] Portal & wthinPortal Property #5

Portal

1. The createPortal function allows you to render certain children into a different part of the DOM, such as displaying a modal or a drawer outside of the current DOM structure.

2. One notable thing about createPortal is we can't use it on the server side. This is why, in the Portal source code of Manine UI, the createPortal function is invoked after the entire component has been mounted.