It wasnarrated that Umm Salamah said:
"The Messenger of Allah (ﷺ)usedto pray Witr with seven or five Rak'ah, and he would not saySalamor speak in between them." (FR)
English reference (FR): Vol. 1, Book 5, Hadith 1192 (FR)
Arabic reference (FR): Book 5, Hadith 1248 (FR)