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Delete references to the tabButton style.
Change all
default-selected-style="tabButtonSelected"
to
default-selected-style="selected".
Delete orientation="horizontal" and orientation="vertical". The menu widget renders a simple unordered list, so the menus are vertical by default. Horizontal menus must be styled with a horizontal menu CSS style (see the maincss.css file). You can specify a horizontal menu style by using the menu-container-style property.
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