@kas yes you can do that!

a[href^="http"]::after {
    content: "🔗";
}

::after { content: "<foo>"} inserts <foo> after the match,
and a[href^="http"] matches a elements that have an href attribute that starts starts with (^=) "http".

That would work as is in patch{work,bay} because they don't use http links internal values, but with http based clients like patchbay, you'd just have another css rule that came after that one that matched localhost hrefs and disabled the link symbol. something like that.

#css-engineering