Two Tabs of the Same Name
When on a Book page, if there aren't enough tabs to form an "Options" menu, but the Book tab is also present, the main tab is called "Book", and the "Add to Book" tab is called "Book". This can be confusing.
Theoretically Group has a same-named tab, even though the "Assign to Social Group" tab will never appear on a Group page that works correctly. However, since tabs also might show the name of a prefix under some configurations, and "Group" could be such a prefix, there may be a more fundamental issue that needs addressing.
Perhaps rather than simply renaming the short-tabs with conflicts, the tab factory should be smart enough to know when two short-tabs have matching text. In that event, it will be ideal if the factory resolved the factory by using the long-tab for each extra instance of the matching text.