Raster Image - Properties

From RealWorld Wiki

The Properties operation is an operation plug-in, which works with raster images and sets canvas size and alpha handling mode for the defalut implementation of the raster image document.

When the automatic alpha mode is activated (the default one), the application tracks if there are any semitransparent pixels and adjusts itself accordingly. For example the Icon from Image transformation determines the background color if there are no transparent pixels.