Some packages require saving twice to launch initially
Some packages require saving twice for the changes to actually apply, or to launch initially. pfflowd is one example, the first save after install on a system where it has never been installed just saves the config and doesn't launch it, the second save correctly launches it.
#3 Updated by Ermal Luçi about 8 years ago
Just for reference the commit https://rcs.pfsense.org/projects/pfsense-packages/repos/mainline/commits/b5b95ddb8bde31ff256c40f7f2174ec460108fbe