Prettier disagrees, as I understand it. Its authors know it's "wrong" to take this: const matrix = [ 1, 0, 0, 0, 1, 0, 0, 0, 1,

Prettier disagrees, as I understand it. Its authors know it's "wrong" to take this: const matrix = [ 1, 0, 0, 0, 1, 0, 0, 0, 1, ] and collapse it onto one line. But their view is that reformatting everything from scratch is more important that such things, and that it's reasonable to add /* ignore */ comments to every single place where you want anything preserved.