I know the config file requires the IPs to listen on to be available at start, however I want to point out a situation in which this is a disadvantage (and maybe hear your suggestions for a solution). I have an android phone, a small android tablet, and a Linux Mint computer. I also have a non-techie girlfriend.
We are currently on the go, and we use the phone connection to navigate internet with the laptop and tablet (much better to have a laptop when you have much to write, or big photos to look at and edit etc.
We connect the phone to the computer via USB, tether the connection and then, if needed, connect the tablet to the computer's ad-hoc wifi. We do this instead of just using bluetooth from the phone to extend the benefits of our privoxy/polipo setup on the computer to the tablet as well, to save expensive and rare bandwidth. Privoxy is set up to work with Polipo. It's set up with the localhost and the IP address assigned by the phone's wired network, say 220.127.116.11.
At boot, the services are started. Polipo goes, but Privoxy fails: "Fatal error: can't bind to 18.104.22.168:8118."
Then we have to restart privoxy manually, which I can do, but not my girlfriend. It also annoys me, since no configuration needs to actually be changed. If we disconnect and reconnect the phone's cable, the network keeps working ok, because the IP offered is always 22.214.171.124, as a further indication that, in this use case, the attitude of Privoxy of requiring the IPs to respond at start is a bug, not a feature.
Thank you for reading (and if you have a solution in mind to share).