TopWinPrio checks every now and then to see what window is active at the moment. When it finds the one, it gives it higher priority than the usual normal priority. Once this window loses focus, topWinPrio gives the window its standard status back.
By default, TopWinPrio gives the active application a priority “AboveNormal”, but not “High” as many programs do. This is due to the balance of giving the active window a higher priority, meanwhile not taking priority from the drivers.
TopWinPrio runs in the background and can be set to start when windows starts, just run it and forget it’s there. TopWinPrio will work in the background without you needing to do anything.