From MozillaZine Knowledge Base
Move or resize existing windows: Allows scripts to change the size or position of the existing window.
Raise or lower windows: Allows scripts to place windows underneath or on top of other windows.
Disable or replace context menus: Allows scripts to disable or change context (right-click) menus.
Hide the status bar: Allows scripts to hide the status bar, as in popup windows.
Change status bar text: Allows scripts to replace the status bar web address (URL) with scrolling text.