I said to Ibn ʿAbbas, "The people are narrating that the Prophet ﷺ said, 'Take a bath on Friday and wash your heads (i.e. take a thorough bath) even though you were not Junub and use perfume'." On that Ibn ʿAbbas replied, "I know about the bath, (i.e. it is essential) but I do not know about the perfume (i.e. whether it is essential or not.) (Using translation from Bukhārī 884)
أَنَّ النَّبِيَّ ﷺ قَالَ «اغْتَسِلُوا وَاغْسِلُوا رُءُوسَكُمْ وَإِنْ لَمْ تَكُونُوا جُنُبًا وَأَصِيبُوا مِنَ الطِّيبِ» فَقَالَ ابْنُ عَبَّاسٍ فَأَمَّا الْغُسْلُ فَنَعَمْ وَأَمَّا الطِّيبُ فَلَا أَدْرِي