The Debian 11 "Bullseye”Will be released in 2021 but as of today we know that the theme he will use is called Homeworld. It theme Homeworld was created by Juliette Taka and is inspired by the German Bauhaus art movement, which began in the late 19th - early 20th century.
Users will see the Homeworld theme in different places when they use Debian 11. One of them will be in the Debian installer.
Homeworld will exist as a wallpaper but also on the login screen.
After an invitation to creation new topics, a total of eighteen selections were submitted. In a poll the projects received 5.613 votes and the Homeworld theme was the top choice of users.
If you have run Debian 8 or Debian 9, you will have come across works by Juliette Taka since she created the themes Lines and softWaves used in these two releases.