Option can be found in game settings.
Sometimes also helps (when both clients are running) going into offline mode on Steam and Uplay, then launching the game.
See here for instruction.
Players who are using AMD FX Series processors may experience FPS drops and freezes, especially with the FX-8350 model.
Please note that a good cooling solution is also recommended in order to avoid overheating issues, should you implement this workaround.
If you've done both of the above and still have 5-7 FPS make sure to disable these overlays (in this order, depending on what you have installed):
If you still need a boost in performance, set process priority to High in the task manager.