Mini Canvas is an additional canvas to display your selected layer at 100% zoom. It’s primarily useful when designing icons so you don’t need to constantly zoom in and out. Additionally, you can “pin” a layer which becomes useful when pinning components. For example, you might pin a tab bar component, with several icon components inside. When making changes to any of the icon components, you’ll always see updates for the tab bar, making it easier to ensure all the icons feel balanced next to one another.
Enjoy!