The deps. changed from the 0.9.12. There are two more, libheif and exiv2. However, all the dep are written here: README.md · master · FA / Siril · GitLab (except for gnuplot that is not needed in the package)
For now, the 1.0 is not ready (lot of work left), the flatpak manifest would be created first for the C I of the gitlab master.