Running Magento CE 2.1.4 here
Got Tax set up correctly, Cart, Checkout, Order backend it all shows correctly added to the grand total
However, it doesn't seem to show up on the Invoice backend despite 'Include Tax In Order Total' being set to 'Yes'
Any help here?
I don't have any checkout/cart related extensions installed, so don't think that could be an issue
Some screenshots
Order Total
Invoice Total