`email.com` is not a reserved domain, incorrect configuration could result in unintentional effects.
`example.com` is reserved by IANA for bogus purposes, see RFC 6761.
* docs: fix typos
* typos: fix typos found by `codespell` across the codebase
* docs: fix `macOS` spelling
* docs: fix `authentification` terminology
"Authentification" is not a thing.
* docs: fix `localhost` typo in example link
* typos: fix in-code typos
These are potentially higher risk, but no other mentions of these typos
show up in the codebase.