I know that this is a really trivial question and probably pretty simple but this is my first mac and lately whenever I open Firefox the browser window opens flush with the left side of the screen, whereas it used to open in the middle. Again, I realize that I should probably just try to overcome my OCD desire for the window to be centered, but I can't help moving it to the center every time it opens. Is there some way (using the green + button perhaps?) to setup the window's default size and position? Thanks in advance.