[jakub_g]

I know. It sounds like a perfect task for AI to do it though (wasn't the whole premise of AI do to mundane things for us), yet they fail to do it, and I need to use an external tool.

[minimaxir]

Alpha is a 4th image channel that 99%+ of images in the training data do not use, so it makes more pragmatic sense to just not allow it.

[Zarathruster]

Weirdly, MSPaint (or whatever it is now) is really good at this (with, I assume, an AI model)