Question: What uncompleted opera was composed by the composer of Il signor Fagotto?

Context articles: Princess Cinderella
Jacques Offenbach
Robin Guarino
Il signor Fagotto
Count Max (1957 film)
Tancredi
Count Max (1991 film)
Missa Cellensis
Il signor Max
Il signor Bruschino

Princess Cinderella (Italian: Cenerentola e il signor Bonaventura ) is a 1941 Italian fantasy-comedy film written and directed by Sergio Tofano.
It is based on the characters of the popular comic strip series Signor Bonaventura, created in 1917 by the same Tofano for the children magazine "Corriere dei Piccoli".
Jacques Offenbach (] ; ] ; 20 June 1819 – 5 October 1880) was a German-born French composer, cellist and impresario of the romantic period.
 He is remembered for his nearly 100 operettas of the 1850s–1870s and his uncompleted opera "The Tales of Hoffmann".
 He was a powerful influence on later composers of the operetta genre, particularly Johann Strauss, Jr. and Arthur Sullivan.
 His best-known works were continually revived during the 20th century, and many of his operettas continue to be staged in the 21st.
 "The Tales of Hoffman" remains part of the standard opera repertory.
Robin Guarino (born April 3, 1960) is an opera and film director.
 She has directed operas such as "The Marriage of Figaro", "Don Giovanni", "Lohengrin", "Così fan tutte" , and "The Magic Flute" at the Metropolitan Opera.
 Also, she has directed at Seattle Opera, Glimmerglass Opera, Chautauqua Opera, Virginia Opera, and Wolf Trap Opera.
 She continues to direct, most recently "L'etoile" and "The Marriage of Figaro" for the Wolf Trap Opera Festival, " La Calisto", "The Magic Flute" and "Iphigénie en Aulide" for Juilliard Opera Center, and at Gotham Chamber Opera, "Il Signor Bruschino".
 She currently holds the J. Ralph Corbett Distinguished Chair in Opera at the University of Cincinnati College-Conservatory of Music."
Il signor Fagotto is a one-act opérette by Jacques Offenbach to a French libretto by Charles-Louis-Étienne Nuitter and Étienne Tréfeu, first performed in 1863.
 The story of a father outwitted and true love winning is set within “a burlesque of musical styles”.
Count Max (Italian:Il conte Max) is a 1957 Italian-Spanish comedy film directed by Giorgio Bianchi and starring Alberto Sordi, Vittorio De Sica and Anne Vernon.
 It is a remake of the 1937 film "Il signor Max" in which De Sica had played the title role.
 This film was itself remade in 1991.
Tancredi is a "melodramma eroico" (opera seria or 'heroic' opera) in two acts by composer Gioachino Rossini and librettist Gaetano Rossi (who was also to write "Semiramide" ten years later), based on Voltaire's play "Tancrède" (1760).
 The opera made its first appearance at the Teatro La Fenice in Venice on 6 February 1813, and because "Il signor Bruschino" premiered in late January, the composer must have completed "Tancredi" in less than a month.
 The overture, borrowed from "La pietra del paragone", is a popular example of Rossini's characteristic style and is regularly performed in concert and recorded.
Count Max (Italian:Il conte Max) is a 1991 French-Italian comedy film directed by Christian De Sica and starring De Sica, Ornella Muti and Galeazzo Benti.
 It is a remake of the 1957 film "Count Max", which was itself a remake of the 1937 film "Il signor Max".
 Both films had starred Christian De Sica's father Vittorio De Sica.
The Missa Cellensis in C major (Hob.
 XXII:8, full title: Missa Cellensis Fatta per il Signor Liebe de Kreutzner) is Joseph Haydn's eighth setting of the mass.
 In German it is regularly named Mariazellermesse.
 It was composed in 1782 and is Haydn's last setting of the mass before his six late great masses.
 Haydn dedicated this work to the pilgrimage of Mariazell in Styria, as he had done with his earlier "Missa Cellensis in honorem Beatissimae Virginis Mariae" which was composed in 1766–1773.
 The mass was commissioned by the officer Anton Liebe von Kreutzner on the occasion of his ennoblement.
Il Signor Max is a 1937 Italian "white-telephone" comedy film directed by Mario Camerini.
Il signor Bruschino, ossia Il figlio per azzardo (Signor Bruschino, or The Accidental Son) is a one act operatic farce (farsa giocosa per musica) by Gioachino Rossini to a libretto by Giuseppe Maria Foppa, based upon the 1809 play "Le fils par hasard, ou ruse et folie" by Alissan de Chazet and E.T.M. Ourry.
 The opera was first performed in Venice at the Teatro San Moisè on 27 January 1813.