Suggest removing older version of documentation on a topic -or- refer to the newer version -or- state in the most recent version what has changed. Example: The Lets Encrypt documentation has changed. The 2018 and older version talks about having to setup a DNS _acme-challenge record. The 2019 version does not mention the need for it (I like that!). But ... which version is the correct one? One would assume the latest but we all make mistakes so clarity through simplification (remove old docs) would be appreciated! Btw, Lets Encrypt feature is great!