[SamBam]

I think it makes perfect sense. CSS is for display, not content. Therefore, anything that gets put in before/after is a display matter only, it's not semantic content. Therefore, it shouldn't be selectable.

[sergeykish]

You forgot about `user-select`

    * { user-select: none }

now entire page is for display. What is content and what is meta decided by consumer, author can guide, medium creates obstacles. <blockquote> does not copy quotes. Some pages present link as <a href=foo>foo</a>, it would be nice to use

    a::after { content: '(' attr(href) ')' }

but it is not selectable. A lot of pages present anchor as <a>¶</a> on hover, can't be done with CSS. What is missing is

    *::before, *::after { user-select: text }

Nope, it does not work.

Best tool so far is XSLT, I've written prototype that mimics CSS syntax

    quote {
      content-before: '"'
      content-after: '"'
    }
    a {
      content-after:  '(' @href ')'
    }
    h2 {
      content-before: <a href=@href>¶</a>
    }

Anyone interested?