show-source.js

(function show_source_code() {
  var url = document.currentScript.dataset.href; if (!url) url = ""
  var text = `<div class="show_source_code"><b><a href="${url}">ORIGIN: ${url}</a></b><pre contenteditable="true" class="show_source"
  style=" overflow-y: scroll; border:1px solid black; padding: 1em; " spellcheck="false" translate="no"></pre></div>`
  document.currentScript.insertAdjacentHTML("afterend", text)
  var code = document.currentScript.nextSibling.firstChild.nextSibling
  fetch(url).then(res => res.text()).then(res => code.textContent = res)
})()