Lightning popover - show nubbin in the right side

Question

I am using popover with lightning:overlayLibrary. The standard side of the nubbin is on the left. and looks like this:

I am trying change it to right. This is how I'm using it:

  component.find('overlayLib').showCustomPopover({
                        body:modalBody,
                        referenceSelector:".mypopover",
                        cssClass:"slds-nubbin_right,no-pointer",
                    })

with the following css:

.THIS.no-pointer .pointer { 
    visibility: hidden !important; 
}

As you could see, I added the classes "slds-nubbin_right,no-pointer" in order to remove the left nubbin and show the right nubbin (as written in the documentation) and this is the result i get:

This is from the documentation:

How can I put the nubbin only in the right side?