“The Messenger of Allah ﷺ used to pray Witr with seven or five Rak’ah, and he would not say Salam or speak in between them.” (Using translation from Ibn Mājah 1192)
أَنَّ النَّبِيَّ ﷺ كَانَ «يُوتِرُ بِخَمْسٍ أَوْ بِسَبْعٍ لَا يَفْصِلُ بَيْنَهُنَّ بِكَلَامٍ وَلَا بِتَسْلِيمٍ»