What short film preceded Coco in theaters?

The short film that preceded Coco in theaters was Olaf's Frozen Adventure. Disney attached the 21-minute Frozen featurette to Coco screenings as a limited-time theatrical presentation beginning with Coco’s 2017 release.

The pairing was unusual because Pixar films traditionally opened with a new Pixar short. Olaf's Frozen Adventure was produced by Walt Disney Animation Studios and follows Olaf as he searches for holiday traditions that will help Anna and Elsa celebrate Christmas.

Its length also drew attention: at about 21 minutes, it was much longer than the short films audiences generally expected before a Pixar feature. Some viewers criticized the extended preshow, especially in Mexico, where cinemas eventually removed it after complaints.

The featurette was initially intended for a television premiere on ABC during the 25 Days of Christmas programming. Its theatrical run ended in early December 2017, making the Coco engagement a limited experiment rather than a permanent Pixar presentation tradition.