Updated 01-Oct-2023
PPAs are personal package archives that allow people to distribute application packages to Ubuntu distributions. Since Ubuntu is based on Debian, and PPA packages are in the .deb format, they can theoretically be used in Debian. However, there are several complications that need to be understood:
- Why PPAs are not recommended for use in Debian (Reddit)
- Extrepo external repositories is a list of external repositories
At the end of the day, I do use I think one PPA for installation, the obsproject / obs-studio program.
If you want to install Firefox on Debian, then another PPA is needed.