PWA Icon

Hi there,
first of all gongrats on your excellent plugin. Everything works as expected. What customizations do I have to do for the icon to show in an full circle on pixel devices? Right now, my favicon is a white logo in a black rectangle. When added to home screen it show a grey circle and the small favicon inside. It would be great if I knew how to customize my favicon to have an android icon full black circle with white logo.
Thank you in advance

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