Is there any way to determine if a clover.intent.action.MERCHANT_TENDER intent has come from the Register app or Sale app? I was thinking of looking at the order line items and if it's just one item called "Sale" then we can probably guess it came from Sale. But then of course that rule might change.
You might be thinking "well the app shouldn't care", but in the case of Payments Plus we need different behavior because there is no support for line items and guaranteed support for a customer facing tender so we're stuck supporting two pretty different ways of doing things under one app. Another solution would be if we had the ability to turn off the merchant facing tender in Sale but not the Register for non-Payments Plus merchants, but I don't think that's possible.