Click event not triggered after focusout event
Thats because it doesn't have enough time to get the click to trigger since the button moves position. You can see the click works if you hold the mousedown and move the mouse to the button and let the click go and you'll see click works.
Either use btn.on('mousedown',f3);
or position the button so it doesn't get moved on focusout
DEMO mousedown
DEMO button positioned
The way click works is that you have mousedown on an element and mouseup on it aswell, thats when it triggers click