The only difference between a novice and a professional is that a professional checks what they are copying to understand it first before allowing it into their codebase.
Novices copy code to avoid having to understand it. Professionals copy code to avoid reinventing the wheel.
Finally found out why I couldn't renew my Let's Encrypt cert.
Did you know fresh installs of Debian Testing come with firewalld installed and enabled to auto-block all incoming connections? Me neither!