When you earn currency, there's a visual update of a big plus the amount and an image of the currency. It's a nice little thing, but the annoying thing is, if I am on a different tab and update the page or navigate to a new page I get the visualisation again. This often creates the impression that I've earned new currency, when it is just a ghost of previously earned currency. This is quite annoying.
I am not sure if it is even possible to fix it so that the update only shows when you actually earn it, and not when you are in a different tab. Ideally that would just be fixed. But even then it might be desirable for some folk to have the option to turn this visualisation off.