Whoops they changed the opening and now it is cute and sad.
It opens on all five(!) of them being best friends and looking at the city and birds. The Senshi are singing their song and being cuter than they have any right to be. Then… it shifts to just Usagi, singing alone. You see the footage of them all walking down the street, together, but the picture gets blurry and it’s fading out fast and the song cuts out early on an unresolved chord.
Anyway that’s enough opening credits meta for today I suppose.