Thanks so much for your answer! Yes, I read about this in your tutorial section “Upgrading SmartMenus jQuery + Bootstrap add-on”.
Yet, I am using the Bootstrap addon with WordPress, so I am not quite sure where to place the <span>. Do you know of any site where SmartMenus is integrated with Bootstrap and WordPress, so I could have a look?
I tried to append the <span> with jQuery, but then the same happens, – clicking on the minus to close the sub-menu links to the parent page. Only if I clock outside the a, then it closes.