Lots posted about this, so searching the forum might be a great place to start.
In short, Ford recommends 1000 miles of less-aggressive and slower driving. Other people say it doesn't matter. Many recommendations one way or another, but not much evidence either way. I decided that it doesn't hurt to take easy for the first 1000 miles, and it might help with long-term durability.
I accidentally found the break in message in the manual! After my daughter and I took the maverick screaming down the freeway for a test run!! Lol! No damage done! Still running great!