Changing the hero icon.

Good day. The white background is related to the fact that you either don't have or haven't configured the alpha channel.

As I understand it, this is more of a bug with different colors of transparent alpha, rather than the fact that it's missing. Transparent pixels in the TF_8888 format should be black, and partial transparency is not supported. White transparent pixels will be displayed as white, not transparent. This can be fixed in a photo editor, but I also struggled with it at one time.