Normative: Adds change-array-by-copy (#2997)

Co-authored-by: Ashley Claymore <[email protected]>
Co-authored-by: Nicolò Ribaudo <[email protected]>
Co-authored-by: Robin Ricard <[email protected]>
Co-authored-by: Michael Dyck <[email protected]>
Co-authored-by: Shu-yu Guo <[email protected]>
Co-authored-by: Jordan Harband <[email protected]>
Co-authored-by: Linus Groh <[email protected]>