### 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.
ERR_FAIL_COND(window_id == DisplayServer::INVALID_WINDOW_ID);
	DisplayServer::get_singleton()->window_set_rect_changed_callback(Callable(), window_id);
	DisplayServer::get_singleton()->window_set_window_event_callback(Callable(), window_id);
	DisplayServer::get_singleton()->window_set_input_event_callback(Callable(), window_id);
	DisplayServer::get_singleton()->window_set_input_text_callback(Callable(), window_id);
	DisplayServer::get_singleton()->window_set_drop_files_callback(Callable(), window_id);
	if (transient_parent && transient_parent->window_id != DisplayServer::INVALID_WINDOW_ID) {
		DisplayServer::get_singleton()->window_set_transient(window_id, DisplayServer::INVALID_WINDOW_ID);
	}
	for (const Window *E : transient_children) {
		if (E->window_id != DisplayServer::INVALID_WINDOW_ID) {
			DisplayServer::get_singleton()->window_set_transient(E->window_id, DisplayServer::INVALID_WINDOW_ID);
		}
	}
	_update_from_window();
	DisplayServer::get_singleton()->delete_sub_window(window_id);
	window_id = DisplayServer::INVALID_WINDOW_ID;
	
	if (focused && transient_parent) {
		transient_parent->grab_focus();
	}
	_update_viewport_size();
	RS::get_singleton()->viewport_set_update_mode(get_viewport_rid(), RS::VIEWPORT_UPDATE_DISABLED);
}
void Window::_rect_changed_callback(const Rect2i &p_callback) {