Portorosso can be seen as an advertisement on a travel agency window in Pixar's previous film Soul (2020).
Alberto's surname, Scorfano, is Italian for scorpionfish. It's commonly used to indicate a person that is not good looking.
In the Marcovaldo's kitchen, the brand of the stove is "Caldino" (little hot), while those of the fridge is "Freddino" (little cold).
The favorite pasta dish in Marcovaldo's house is "trenette al pesto" - it's the flagship dish of Genoa, the city where director Casarosa comes from. Trenette are a kind of flat spaghetti, pesto is a sauce made out of basil, parmesan, pine nuts, garlic, and olive oil.
Director Enrico Casarosa stated that he drew inspiration from the films of Hayao Miyazaki when creating the film. The character Luca's original last name was Portorosso, a nod to Miyazaki's Porco Rosso - O Último Herói Romântico (1992) (in English, Porco Rosso). In the final version of the film, the character's surname was changed and the name of the town was changed to Portorosso.