This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
Emanuel Bachʼs character piece "Bergius" (Bergius, Wq. 117/20) is a refined and elegant work included in the 1765 collection of "Character Pieces." It is set in F major, characterized by its bright and serene melody and lively rhythm. The title "Bergius" likely refers to a specific individual, possibly a friend or patron of Emanuel Bach, and is thought to express dedication or respect towards that person. The piece prominently features the traits of the Empfindsamer Stil (Sensitive Style), and despite its brevity, it stands out for its lyricism and individuality. Performers are required to bring out the elegance and poetic nuances of this piece through their expressive capabilities.