I now get a white box when launching firefox- iMac 27" late 2013
How do I get rid of the white box?
Alla svar (1)
Where does the box appear? Does it block you from using Firefox?
If there is a mostly blank box centered over the display with a gray bar, checkbox and a question mark, that may be the AOL Toolbar issue. Updating AOL might resolve that issue, or you could remove/disable the toolbar.
If there is a different box, perhaps it is some kind of partially blocked advertising. Could you post a screenshot of how the box appears? This article has suggestions: How do I create a screenshot of my problem? Please cut out or blur any sensitive information in the image before attaching it to a reply.