[mdpm]

HTML5 is no longer XHTML compliant. There were a suite of tools that worked with markup that weren't browsers. This allowed the web to be the input, output, and middle of other chains of tools. It was sort of like removing '|' from the CLI.

[hollowturtle]

I still don't get it, HTML5 lets you write your documents in XHTMLish way. The spec doesn't care, you just decide. And tools should still work as expected

[hollowturtle]

And BWT it was xhtml to broke backward compatibility "XHTML is not compatible with the IE8 and other older versions of the browsers. HTML5 is capable of using XHTML style tags but not vice versa. While writing code in XHTML, there are several restrictions that the developers need to adhere to"

[mdpm]

HTML5 documents are not XML; this means that tooling that isn't a browser, or isn't 'HTML aware' became excluded. The web 'special cased' itself at this point, and HTML and common data processing pipelines of the time parted ways, this is my only point.

[hollowturtle]

You can't compare it to the pipe operator, you can still write xhtml valid documents in html5

[TeMPOraL]

But most of HTML5 documents aren't written like that, which is the problem.