@jdaviescoates totally confusing for sure. Not cloudron's fault completely as TLS is just an update to SSL. The problem comes from old software I think where SSL (the verb) is still being used where TLS should be. Both are technically the same, one is just newer.
Or at least that is what google would suggest lol. Either way, you can never have too many docs so an update to specifically call this out when working with SMTP ports would be useful.