UITab memory leak

I have the following view hierarchy in my app: [UINavigationController] -> [MainViewController] -> [MyTabBarController] -> [DashboardViewController]

In my MainViewController I have a button that pushes the MyTabBarController onto the navigation controllers stack. In the tab bar controller I only have one tab in this example showing the DashboardViewController.

That all works fine, and when I tap the back button on MyTabBarController, everything works fine and the MainViewController is shown again. The UI works exactly how I want it, but when I load up the 'Debug Memory Graph' view, I can see that my DashboardViewController is still in memory and it seems the UITab has a reference to it. The MyTabBarController is NOT in memory anymore.

MyTabBarController is very simple:

class MyTabBarController: UITabBarController {

  override func viewDidLoad() {
    super.viewDidLoad()
    
    self.mode = .tabSidebar
    
    var allTabs:[UITab] = []
    
    let mainTab = UITab(title: "Dashboard",
                        image: UIImage(systemName: "chart.pie"),
                   identifier: "dashboard",
       viewControllerProvider: { _ in
                                 return UINavigationController(rootViewController: DashboardViewController())
                               })
    allTabs.append(mainTab)

    setTabs(allTabs, animated: false)
  }
}

And the DashboardViewController is empty:

class DashboardViewController: UIViewController {
}

The only reason I created as a seperate class in this example is so I can easily see if it's visible in the memory debug view.

I have uploaded the simple sample app to GitHub: https://github.com/fwaddle/TabbarMemoryLeakCheck

Anyone have any suggestions?

Here is a screen grab of the memory debug view showing the UITab having a reference to the DashboardViewController even though MyTabBarController has been dealloc'd: