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Where are favorites stored?
Favorites Individually favorited portlets are stored in a DLM fragment folder 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).
Favorited collections (currently) are DLM fragment tab-level folders of type="regular", i.e. regular old tabs. This is currently to make Favorites compatible with, a different view on, your regular old layout.
Thoughts: Possibly Favorites should instead display tab-level folders of type="favorites-collection" as such collections. Possibly this should be a portlet preference allowing both approaches. Which you'd want probably depends on whether you're trying to use Favorites instead of or along side of traditional tabs, whether and what layouts you're carrying forward from prior uPortal versions in your implementation, whether you're trying to offer respondr alongside of or instead of universality. Anyway, Favorites doesn't do any of that yet – currently it's hard-coded to consider tabs of type="regular" as collections of favorites. Wisconsin in particular will feel that as a pain point once there's a "Welcome tab" landing page in their redesigned portal. 
Viewing
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.)
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