Muawiya offered one rakʿa witr prayer after the ʿIsha prayer, and at that time a freed slave of Ibn ʿAbbas was present. He (i.e. the slave) went to Ibn ʿAbbas (and told him that Muawiya offered one rakʿa witr prayer). Ibn ʿAbbas said, "Leave him, for he was in the company of Messenger of Allah ﷺ."
دَعْهُ فَإِنَّهُ صَحِبَ رَسُولَ اللَّهِ ﷺ
I read out (this tradition) to Sa'id b. Ya'qub al-Taliqini, and I said to him: Ibn al-Mubarak transmitted (this tradition) to you from Sa'id Abi Shuja' who said: 'Uthman b. Sahl b. Rafi' b. Khadij narrated it to me saying: I was an orphan being nourished under the guardianship of Rafi' b. Khadij and I performed Hajj with him. My brother 'Imran b. Sahl then came to me and said: We rented out land to so-and-so for two hundred dirhams. He said: Leave it, for the Prophet ﷺ forbade renting land.
دَعْهُ فَإِنَّ النَّبِيَّ ﷺ نَهَى عَنْ كِرَاءِ الأَرْضِ