I've been working on an macOS app for a while. And recently Apple released the first beta version of Big Sur, so I changed my app icon into rounded rectangle shape, just like every other apps in Big Sur.
Now I wonder if it is possible to let my app use rounded rectangle shape in macOS 11.0+, and use another icon in previous versions?
I noticed that Apple's Developer.app is already doing this.
EDIT: I noticed that Apple's Developer.app app icon doesn't change automatically. You have to reinstall it from the App Store.