### Godot version

4.1.dev (dc625bcbfc5b587ba8867481ee7a1f6a567c25d0)

### System information

Mageia 9, Linux

### Issue description

When importing a project in current `master`, the following error is raised for each asset that gets imported:
```
Attempting to parent and popup a dialog that already has a parent.
```

It seems to be raised once per asset, caused by the progress dialog.

CC @bruvzg

### Steps to reproduce

- Import a new project in Godot that contains importable assets, e.g. https://github.com/RPicster/godot4-demo-desert-light

### Minimal reproduction project

See above.
} else if (transient_parent->exclusive_child != this) {
				ERR_PRINT("Making child transient exclusive, but parent has another exclusive child");
			}
		}
	}
	
	if (transient_parent->window_id != DisplayServer::INVALID_WINDOW_ID && window_id != DisplayServer::INVALID_WINDOW_ID) {
		DisplayServer::get_singleton()->window_set_transient(window_id, transient_parent->window_id);
	}
}
void Window::set_transient(bool p_transient) {
	ERR_MAIN_THREAD_GUARD;
	if (transient == p_transient) {
		return;
	}
	transient = p_transient;
	if (!is_inside_tree()) {
		return;
	}
	if (transient) {
		_make_transient();
	} else {
		_clear_transient();
	}
}
bool Window::is_transient() const {
	ERR_READ_THREAD_GUARD_V(false);
	return transient;
}
void Window::set_exclusive(bool p_exclusive) {