Hence HTML as a mere vocabulary making use of SGML's facilities didn't need to define its own ad-hoc mechanism.
Btw the <?php ...> construct is also derived from SGML. In SGML terms it's a "processing instruction" rather than an "entity reference", the latter being the basic means for content inclusion.
https://web.dev/articles/imports
Been there, tried that.
Introduced in 2014 (Chrome 36) Deprecated 2018 (Chrome 70) Retired 2019 (Chrome 73)
<!-- #include file="header.html" -->
(but yes- I used these a lot like 25 years ago)
Why is there no direct support for templating in HTML itself?
Eg some template feature creates a security issue and has to be disabled, which invalidates all the old HTML that used it.
There’s also just not a super great reason to do it. It’s not all that different from pre-templating like Hugo or doing it server-side like Django. You get to offload some compute, but HTML templating isn’t usually the bottleneck.
This might be the worst argument for anything I've read this week, there's got to be a name for this logical fallacy