Using observe in a modal window (Swift, macOS)

MongoDB Atlas App Services & Realm
1

This may be a Realm bug, or OE, but I am having an issue setting up a realm observer in a modal window (not a sheet).

TL;DR
When using Realm Notifications, the .observe’s initial event fires correctly when a view controller is shown as a sheet, but does not fire when shown as a modal window until the window is actually closed.

Here’s the details;

Here’s the setup. I have a window with two buttons; button 0 creates a sheet from a viewController and displays it. button 1 does the same thing but displays it as a modal window.

It’s super simple but here’s the main view controller (MainVC)

Main VC

and then the second SecondVC being shown as a sheet)

Second VC
Second VC798×450 59.8 KB

or as a modal window

Modal
Modal1210×362 81.3 KB

The add observer code in the second view controller adds an observer to some objects

func addObserver() {
   print(#function)
    let realm = try! Realm()
    let people = realm.objects(PersonClass.self)

    // token is a class var token: NotificationToken?
    self.token = people.observe { changes in 
        switch changes {
            case .initial:
                print("initial load")

            case .update(_, _, _, _):
                print("update")

            case .error(let error):
                fatalError("\(error)")
            }
        }
    }
}

Here’s the issue:

When showing as a sheet and clicking the Add Observer button, as expected we can see the observer is added and the .initial change fires (output shown in the console)

Realm version: 10.5.0
2021-01-15 14:33:11.501816-0500 Realm 5[33396:7693838] Metal API Validation Enabled
addObserver()
initial load

However, when performing the exact same steps when showing the SecondVC as a modal window, it does not fire the initial load

Realm version: 10.5.0
2021-01-15 14:35:17.940594-0500 Realm 5[33436:7696961] Metal API Validation Enabled
addObserver()

But if I then dismiss the SecondVC when it’s showing as a modal window, that event fires when it closes.

Is this a Realm thing or just me overlooking some inherent difference in how modal windows work?