Ubisoft took note of Assassin’s Creed: Unity graphical problems straight away and made an official blog to address whatever issues that the players were facing.
To improve the performance even further, Ubisoft has created a special thread on its official forums, where they will post the issues and provide their fixes.
Every single bug identified thus far has been listed on this forum under the labels “Fixed”, “Working On It” or “Workaround.”
One of the biggest issues that players have been encountering when playing Assassin’s Creed: Unity is the dropping of frame rates.
Ubisoft has provided a workaround for it and has suggested that you must disable your internet when you are playing a single player campaign. This workaround has been working quite well for the players.
Sometimes, Arno just fell through the buildings; this issue has been fixed for PlayStation 4 and PC users, while Xbox One players never encountered it.
Plenty of other small and big issues are being worked on at the moment, and Ubisoft assures that a fix for them will be out sooner rather than later.
If you are facing any problem that is not listed on the forums or live blog, then you should report them to Ubisoft using the above links.