Great add on and fantastic support! No more weirdly proportioned images!
Responsive websites are great but not always, sometime you have a certain space for an image and depending on the device or screen your using, the result could differ allot. Sometimes the image is too small, be clipped or completely missing, or just really awkward looking.
This add-on is designed to make sure that you as a designer can make sure your image looks great on any device or screen!
This is done by ensuring that the 'spare' parts of your image (negative space) are cropped out before the important part that you select.