Which treaty or pledge took place under a tree at Hudaibiya, where companions swore allegiance to avenge the rumored death of Hazrat Uthman (RA)?

Explanation

Bait-e-Rizwan (Pledge of Satisfaction) occurred at Hudaibiya in 6 AH. When rumors spread that Hazrat Uthman (RA) had been killed by the Quraish while negotiating, Prophet Muhammad (PBUH) took a solemn pledge under an acacia tree from approximately 1,400 companions to fight until death. Allah praised these believers in Surah Al-Fath (Verse 18).