Is the new San Francisco Paid Parental Leave taxable in CA and Fed even though it is considered "supplemental compensation" paid from the employer to the employee?

San Francisco now requires  “employers to pay ‘Supplemental Compensation’ equal to the difference between the employee’s California Paid Family Leave benefit and the employee’s normal gross weekly wages such that the employee
receives 100% of their weekly salary." Is this considered wages or PFL for CA taxes?