[rezonant]

We've come so far. Using a language from the 60s to write markup in a language from the 90s all so we can feel good by avoiding writing imperative code in another language from the 90s.

Seriously though, why can HTML not have a client side include?

[lelanthran]

Thankfully you can do it now in a custom elements. I used one, I assumed everybody else would have one by now, too

[colanderman]

You can do client-side include with XSLT, which (surprisingly!) all major browsers support.