A thumbnail image is a small, "thumbnail-size" image that is often a smaller version of a larger image that lets you preview the image before opening or using it. Any time you mark up an image in Guru's Viewing pane, a thumbnail image is automatically created in the Thumbnail Tray pane.
To recall any one of the thumbnails to the Viewing pane
Click the desired thumbnail in Guru.
To play animations that have been saved to the Thumbnail Tray pane
Click the thumbnail in Guru, and then click the Play button.