Putting a closed-source application on Flathub is such a pain. Users of our app even request Flatpak support aggressively [0]. Yet uploading pre-built binaries, which is common for most package managers, isn't supported out of the box by Flathub. A direct upload option would simplify so many things...
[0] https://github.com/riok/Kreya/issues/64#issuecomment-1837278...