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# tabBarController(_:sidebar:update:)

Called whenever the sidebar item’s `configurationState` changes or the item is reconfigured.
The passed in item will accrue all modifications until the delegate requests for a new sidebar
item from the delegate method `tabBarController:sidebar:itemForRequest:`

```
optional func tabBarController(_ tabBarController: UITabBarController, sidebar: UITabBarController.Sidebar, update item: UITabSidebarItem)
```

---

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