New GNOME dialog on the right:
Apple's dialog:
They say GNOME isn't a copy of macOS but with time it has been getting really close. I don't think this is a bad thing however they should just admit it and then put some real effort into cloning macOS instead of the crap they're making right now.
Here's the thing: Apple's design you'll find that they carefully included an extra margin between the "Don't Save" and "Cancel" buttons. This avoid accidental clicks on the wrong button so that people don't lose their work when they just want to click "Cancel".
So much for the GNOME, vision and their expert usability team :P
If you place "Discard" and "Cancel" next to each other, without a margin in between, is easier a user looking to click on "Cancel" to click on "Discard" and lose a document. This is more common than people think and that's why Apple added the margin there and also why any good UX manual tells you to add a margin for destructive operations like that one.