Doesn't work if e-d-s is not installed on the system
When I had installed the flatpak version, I can not add tasks and tasklists. it showed the error ".service file not provided". After I installed e-d-s through the package manager (pacman) it worked.
But why e-d-s cannot be included into the flatpak itself? Calendar, Contacts, Geary, etc. don't need this.