I am trying to
test a new program with 2 interfaces "ActionListener" and "ControllerEventListener". What I expect from the program during the execution would be that when I run the program, a GUI appears with a button on it. After I click on the button, the there would be a chain of sound appearing along with the random animation on the GUI. However, there is also an unwanted button popping up at the left corner of the GUI. Why does that button appear and why is it in the left corner? Thanks in advance.