Not working with goldmark 1.7.0

[kpym]

This extension looks to be broken with at least goldmark 1.7.0.

Here is an example of code and the resulting output (available in the golang playground).

package main

import (
	"log"
	"os"

	"github.com/mdigger/goldmark-attributes"
	"github.com/yuin/goldmark"
)

var example = `
# title {#main}

{#id .class1}
text
`

func main() {
	var md = goldmark.New(attributes.Enable)
	var source = []byte(example)
	err := md.Convert(source, os.Stdout)
	if err != nil {
		log.Fatal(err)
	}
}

<h1>title {#main}</h1>
<p>text</p>

This was reported in this related issue.