This is narration says when Moawiya bin Abu Sufyan used to appoint a Governor, he used to give orders to his Governors to curse on Imam Ali(as) in mosques and public places. When he appointed Sa'ad bin Abi Waqas he asked for it. Sa,ad bin Abi Waqas said “there are three virtues of Ali I cannot do so”, Please read those 3 prominent virtues of Imam Ali in this narration.
Arabic
This is very well proven fact (unfortunately) that Moawiya started cursing on Imam Ali(as) in mosques (Friday and Eid sermons). It remained for many decades until the time of Umar bin Abdul Aziz (Ummayad caliph), he stopped it.
This is also a proven reality that along with cursing on Imam Ali (as) Moawiya fought war with Imam Ali, thousands of people got killed. We discussed these things in our articles, we cannot talk much in here about Moawiya's enmity with Imam Ali.
Please read from Nissaie, The Holy Prophet said " Anybody who curse Ali, curses me".