Play: Starts animation of your GIF in the ‘Preview' area.
The Toolbar button equivalent is .
Stop: Stops the animation.
The Toolbar button equivalent is .
Optimize: Opens the ‘Optimization options' dialog window allowing you to choose which optimization methods should be applied to your animated GIF, including optimizing color map, cropping unused transparent areas, and merging pixels of the same color.
Using the ‘Optimize' command helps you significantly reduce the image file size.
The Toolbar button equivalent is .