The combination of the behavior of the toggle comment shortcut and the auto-indent shortcut cause a bit annoying results. For example, given this code:

Item {
  Item {
    property string prop1: ""
    property string prop2: ""
  }
}

Now let's comment out the property prop2 using Ctrl+Shift+7. Results in:

Item {
  Item {
    property string pro1: ""
//    property string prop2: ""
  }
}

Ok. Now Let's wrap the whole thing in another item

Item {
Item {
  Item {
    property string prop1: ""
//    property string prop2: ""
  }
}
}

And select everything and use Ctrl+i to clean up the indentation:

Item {
  Item {
    Item {
      property string prop1: ""
      //    property string prop2: ""
    }
  }
}

Now the auto-indent moves the commented out property in too much.

Obviously in this constructed mini example it's not so much of a big deal and in C++ I never really noticed this badly, but especially in QML where one moves Items around quite a lot to move them into a layout, wrap them into a colored Rectangle for visual debugging, comment out something temporarily etc, this causes the developer to having to fix the indentation quite a lot.