DALLAS—Give Southwest Airlines credit. The lighthearted airline that cracks in-flight jokes can make even the most dramatic changes seem like a win for all travelers. The airline paraded people through a shiny new Boeing 737 MAX 8 decked out with rows of cushy extra-legroom and “preferred” seat sections,

From the outside, the new Southwest Airlines 737 MAX Jet looks like all the others. But inside is where passengers will notice some major changes.

TPG got a look at a new Southwest Airlines aircraft outfitted with its first-ever extra-legroom seats and refreshed cabin interior.