Externalize license footer script to satisfy CSP

theme/license-footer.js

@@ -0,0 +1,76 @@
+(function () {
+  var URL_HREF = "https://creativecommons.org/licenses/by-sa/4.0/";
+  var PREFIX =
+    "Content on this site by Baby Ghosts Studio Development Fund is licensed under CC BY-SA 4.0. " +
+    "To view a copy of this license, visit ";
+
+  function isDoc() {
+    return location.pathname.indexOf("/doc/") === 0;
+  }
+
+  function findTarget() {
+    var pm = document.querySelector(".ProseMirror");
+    if (pm && pm.parentElement) return pm.parentElement;
+    return (
+      document.querySelector("article") ||
+      document.querySelector("[role=main]") ||
+      document.querySelector("main")
+    );
+  }
+
+  function render() {
+    var existing = document.querySelector(".cc-license-footer");
+    if (!isDoc()) {
+      if (existing) existing.remove();
+      return;
+    }
+    if (existing) return;
+    var target = findTarget();
+    if (!target) return;
+    var footer = document.createElement("footer");
+    footer.className = "cc-license-footer";
+    var p = document.createElement("p");
+    p.appendChild(document.createTextNode(PREFIX));
+    var a = document.createElement("a");
+    a.href = URL_HREF;
+    a.target = "_blank";
+    a.rel = "noopener noreferrer";
+    a.textContent = URL_HREF;
+    p.appendChild(a);
+    footer.appendChild(p);
+    target.appendChild(footer);
+  }
+
+  var pending = false;
+  function schedule() {
+    if (pending) return;
+    pending = true;
+    requestAnimationFrame(function () {
+      pending = false;
+      render();
+    });
+  }
+
+  ["pushState", "replaceState"].forEach(function (m) {
+    var orig = history[m];
+    history[m] = function () {
+      orig.apply(this, arguments);
+      schedule();
+    };
+  });
+  window.addEventListener("popstate", schedule);
+
+  function start() {
+    new MutationObserver(schedule).observe(document.body, {
+      childList: true,
+      subtree: true,
+    });
+    schedule();
+  }
+
+  if (document.readyState === "loading") {
+    document.addEventListener("DOMContentLoaded", start);
+  } else {
+    start();
+  }
+})();