DayBack Calendar and FileMaker 16
Once you've made this change, any version of DayBack from 9.90 onward works in FM16. This might be a great time to make sure you have the latest version of DayBack as it keeps getting better with in-app updates: latest version.
Except for Printing
FileMaker 16 no longer prints the content of web viewers meaning you won't be able to print the calendar unless you take a screenshot of it and print that. If you think FileMaker should change this, please log a feature request here.