Pointer coordinates are wrong in the browser fullscreen API

[eonarheim]

Steps to Reproduce

var game = new ex.Engine({
  width: 800,
  height: 600
});
game.screen.goFullScreen();

var pointer = new ex.Actor({
  width: 25,
  height: 25,
  color: ex.Color.Red
});
game.add(pointer);

game.input.pointers.primary.on('move', (ev) => {
   pointer.pos = ev.worldPos;
});

Expected Result

Pointer actor should line up with cursor in fullscreen

Actual Result

Pointer actor does not line up with cursor in fullscreen

Environment

• browsers and versions: Chrome/Firefox Latest
• operating system: N/A
• Excalibur versions: Latest

Current Workaround

None