dovecot IMAP not working on iOS because of Let’s Encrypt certificate problem

So I was having an issue with the mail app in my iPhones not being able to get IMAP email from my dovecot server.
Turned out I needed to change my dovecot config from this:

ssl_key = </etc/dovecot/mail.{{ domain }}.key
ssl_cert = </etc/dovecot/mail.{{ domain }}.crt
ssl_ca = </etc/dovecot/mail.{{ domain }}.chain.pem

to this:

ssl_key = </etc/dovecot/mail.{{ domain }}.key
ssl_cert = </etc/dovecot/mail.{{ domain }}.chain.pem

Input keyboard for decimal input on iPhone

So I needed to adjust a value (the odds of a horse winning a race) that has a fractional part and an integer part (i.e. a ‘double’, or ‘float’). The standard numeric input on an iPhone doesn’t include a decimal point, so I needed to trigger a different input device.

I ended up with this:

<input type="number" pattern="[\d\.]*" step="0.01" inputmode="numeric">