Prevent client uploading images too big or too small

If a client uploads a massive image is there a way to automatically resize it to something that doesn’t take up all their hosting space?

And, if they try and upload a mega small image they get a warning or are preventing from doing so?

See:

In the file blueprint I can set maxsize and minsize. What happens if someone tries to upload an image above or below these sizes? Will the image get automatically resized, or simple rejected?

I see the plugin will be a core part of Kirby 4. I might wait till that comes out…

Rejected. That’s why I suggested the plugins for images that are too big.