Are MobX actions allowed to show a confirm dialog, or navigate to a new screen? More generally, can actions touch ui?

I am refactoring MobX in large-scale applications. Since it is big, making the code clean is very important.

There is an action that does the following (simplified):

@action myAction() {
  var data = await api.getSomeDataFromServer();
  
  if (data.warnUser) {
    var userAgrees = await showConfirmDialog('Hey, are you really sure?'); // #1
    if (!userAgrees) return;
  }

  someOperations(data);

  Navigator.push('/another_page'); // #2
}

I am worried whether the #1 and #2 are OK or not. The reason is that, IMHO mobx has a UI - action - state triad (as is seen in the figure below by the mobx book). Thus, Actions should modify the State instead of the UI directly. But in #1, the Action directly shows a dialog – which is UI; in #2, the Action directly navigates to another page – which is also UI related.

In short, can MobX’s actions directly “touch” and manipulate the uis?

I have made some searches about this and is quite confused now. Thanks for any suggestions!

Remark: I tag it as both Flutter and JavaScript, because indeed I am using Flutter but this question applies to the JS version of MobX as well.

Remark: Following is the diagram from the mobx book.