Document that username/password in SMTP and database config must be urlencoded
Some characters are unsafe to use in configuration variables that are URLs.
EMAIL_CONFIG=smtp+ssl://email@example.com:firstname.lastname@example.org:465 will not work as expected because the username is an email, and
@ isn't a safe char for use in URLs.
Such usernames and passwords must be urlencoded, for instance using the snippet below:
python3 -c 'import urllib.parse; print(urllib.parse.quote_plus("email@example.com"))' noreply%40domain.net