I use Macbook. Every time I use Firefox, there will always be a pop-up with Firefox logo on the left and Application folder on the right with the arrow in between both, which usually means I have to put it in my Application folder and which has already been done. But it still keeps appearing every single time I use but it won't appear again when i close instead of quitting it. But when i quit the application & start Firefox again, the blue box appears. How do I get rid of it?