New document windows should open horizontally centered and should display as much of the document content as possible. The top of the document window should butt up against the menu bar (or the application’s toolbar, if one is open and positioned below the menu bar). Subsequent windows should open to the right 20 pixels and down 20 pixels. Make sure that no part of a new window overlaps with the Dock.
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For nondocument windows, the preference is to open new windows horizontally centered.... The vertical position should be visually centered: The distance from the bottom of the window to the top of the Dock (if it’s at the bottom of the screen) should be approximately twice the distance as that from the bottom of the menu bar to the top of the window. Subsequent windows are moved to the right 20 pixels and down 20 pixels. Make sure that no part of a new window overlaps with the Dock.
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If a user changes a window’s initial size or location, maintain the user’s choices the next time the associated file or window (in the case of a single-window application) opens. If a user opens, moves, and closes a document window without making any other changes, save the new window position....
