The vast majority of scholars hold that all these forms are permissible, including praying witr as three rak‘ahs with a single salām, as established in the Sunnah. However, these hadiths did not reach all the jurists. Some therefore disliked praying witr as three joined rak‘ahs resembling the Maghrib prayer, as reported from Mālik and some Shāfi‘ī and Hanbalī scholars. Others disliked praying witr in any other form, as reported from Abū Hanīfah. Still others disliked praying witr as five, seven, or nine joined rak‘ahs, as stated by some followers of al-Shāfi‘ī and Ahmad, and by Mālik. The correct view is that when the imam follows any practice established in the Sunnah and offers witr in any of the forms mentioned, those praying behind him should follow him in this. Allah knows best.
He was also asked about praying two rak‘ahs after witr.
He replied:
As for praying two rak‘ahs after witr, Muslim narrated in his Sahīh concerning the Prophet, may Allah bless him and grant him peace:
“He would pray two rak‘ahs after witr while seated.”
This was also narrated from Umm Salamah through some authentic chains of transmission:
“He would do this when he prayed witr as nine rak‘ahs.”
For he used to pray witr