The intention behind this is dropping existing behaviour (XSLT support) and that will break at least some websites. I was saying that when they created HTML 5 they went to great lengths to preserve the HTML parsing behaviour, resulting in the complex parsing and tree construction rules. This is because their goal was to preserve compatibility with existing websites.
I could have chosen a better example like quirks mode. My point was that they could have simplified the parser logic and implementation buren by dropping that. But they didn't.
They even went to great lengths to parse existing XML content (SVG, MathML, and XLink) in HTML documents without supporting namespaces.
So dropping XSLT support here is purely because they don't want to put the effort in implementing their own XSLT engine (in a "safer" language if they need to), or to properly support the maintenance of the open source lbraries they rely on. And dropping XSLT goes against why HTML 5/LS was originally created, which was to support all existing HTML and web content no matter what they looked like.
> My point was that they could have simplified the parser logic and implementation buren by dropping that. But they didn't.
You’re right, and I think this is possibly the biggest mistake the HTML5 standards process ever made. They got that one badly wrong. Strict XML-based parsing was the clearly correct solution informed by many years of Postel’s Law constantly fucking the web up with incompatibilities and security vulnerabilities.
> So dropping XSLT support here is purely because they don't want to put the effort in implementing their own XSLT engine
That’s not the whole answer; they think the benefits don’t justify the effort, and I agree with that.
> And dropping XSLT goes against why HTML 5/LS was originally created, which was to support all existing HTML and web content no matter what they looked like.
That wasn’t why HTML5 was created. That makes no sense; you don’t need a new format to preserve the status quo.
I could have chosen a better example like quirks mode. My point was that they could have simplified the parser logic and implementation buren by dropping that. But they didn't.
They even went to great lengths to parse existing XML content (SVG, MathML, and XLink) in HTML documents without supporting namespaces.
So dropping XSLT support here is purely because they don't want to put the effort in implementing their own XSLT engine (in a "safer" language if they need to), or to properly support the maintenance of the open source lbraries they rely on. And dropping XSLT goes against why HTML 5/LS was originally created, which was to support all existing HTML and web content no matter what they looked like.