What does the timer next to XP mean? (Assassin's Creed: Syndicate)

You have an increase in experience, +10 percent in my opinion. When it is zero, then more than +10 percent will not be.

It was reset to zero for me, but then it resumed for some reason

pirate as it should be)

Guys, how can I disable this DLC? And then I went 45%, and already 10 lvl. I want to start over but without this timer. Maybe someone knows what needs to be removed from the folder?