DrHofman submitted a pull request in October addressing this same issue (#1081) (DrHofman/mootools-more@9d8e68d#commitcomment-800590), but I believe this is a better solution.
Fix for #1081.
Where is rowAfterEndRow used?
Fix for tabs/spaces, and the fact that we're not using rowAfterEndRow.
Whoops! I've fixed the missing reference to rowAfterEndRow.