I say, and with God's success: It is obligatory to wash it; because the white area is included in the definition of the face, and it was not covered by hair, so it remains obligatory to wash as it was. Refer to: Al-Maghrib, p. 308, Al-Bada'i 1: 4, Al-Ikhtiyar 1: 13, Fath Bab Al-Inayah 1: 42, Sharh Al-Wiqayah p. 73, and Al-Maraqiy p. 98, and God knows best.