'Wonder Woman 1984' has a musical 'Batman v Superman' Easter egg

For the most part, Wonder Woman 1984 feels completely disconnected from any larger efforts to build out the DC cinematic universe. There's no present-day framing device, no time-traveling messages from the Flash, no wink-wink visits to Wayne Enterprises or S.T.A.R. Labs. 

However, there is a callback to another DC film in the...