How to preview image on Xmind desktop

Hello. My group plans on sharing mindmaps so we can edit each other's. When inserting an image into a subtopic, how do I go about previewing/expanding the image to full screen?

Also, is there an export version for non-Xmind users, where they can preview/expand images of the mindmap after export? Such as a pdf where you can double-click the image and it goes full screen?