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Favorites are stored in a DLM fragment of type="favorites". Since it's a goofy non-regular type, it won't be rendered in traditional spots in the layout (it's not a tab).
Viewing
Edit UI lists favorites.VIEW mode UI lists favorites. Users can click favorited portlets to launch that portlet by fname with MAXIMIZED window state. Users can click Collections of favorites and something not yet fully determined happens. (Maybe that lists the collected portlets so they can be individually launched in maximized window state? Maybe that launches rendering of that tab as a respondr-styled tab? Unclear.)
Editing
Edit UI lists all favorites, collections first then portlets.
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