If you have any difficulties uploading the image, you can follow this
link. Since this is beside the whole point of the question, I have just provided a link.
As I have however mentioned in my comment, the additional button is the result of another application installed on your machine that is interfering with your application. There appears to be nothing you have included in your code that will create this button. Therefore, when providing this application to other people / computers, the additional button should not be present :)