[main]: Update mkdocs to zensical

docs/javascripts/mathjax.js

@@ -1,27 +1,87 @@
-window.MathJax = {
-  tex: {
-    inlineMath: [["\\(", "\\)"]],
-    displayMath: [["\\[", "\\]"]],
-    processEscapes: true,
-    processEnvironments: true
-  },
-  options: {
-    ignoreHtmlClass: ".*|",
-    processHtmlClass: "arithmatex"
-  },
-  startup: {
-    typeset: false,
-    ready() {
-      MathJax.startup.defaultReady();
-      // Subscribe only after MathJax is ready, including on instant navigation.
-      MathJax.startup.promise.then(() => {
-        document$.subscribe(() => {
-          MathJax.startup.output.clearCache();
-          MathJax.typesetClear();
-          MathJax.texReset();
-          MathJax.typesetPromise();
-        });
-      });
+(() => {
+  const rendererUrl = new URL(
+    "../assets/vendor/mathjax/tex-mml-chtml.js",
+    document.currentScript.src
+  );
+  const assetRoot = new URL(".", rendererUrl).href.replace(/\/$/, "");
+  let loading;
+  let revision = 0;
+  let rendering = Promise.resolve();
+
+  function loadMathJax() {
+    if (loading) {
+      return loading;
     }
+
+    window.MathJax = {
+      loader: {
+        paths: {
+          mathjax: assetRoot,
+          sre: `${assetRoot}/sre/mathmaps`
+        }
+      },
+      tex: {
+        inlineMath: [["\\(", "\\)"]],
+        displayMath: [["\\[", "\\]"]],
+        processEscapes: true,
+        processEnvironments: true
+      },
+      options: {
+        ignoreHtmlClass: ".*|",
+        processHtmlClass: "arithmatex"
+      },
+      chtml: {
+        fontURL: `${assetRoot}/output/chtml/fonts/woff-v2`
+      },
+      startup: {
+        typeset: false
+      }
+    };
+
+    loading = new Promise((resolve, reject) => {
+      const script = document.createElement("script");
+      script.src = rendererUrl.href;
+      script.async = true;
+      script.onload = () => {
+        window.MathJax.startup.promise.then(() => resolve(window.MathJax), reject);
+      };
+      script.onerror = () => {
+        loading = undefined;
+        script.remove();
+        reject(new Error(`Failed to load MathJax from ${rendererUrl.href}`));
+      };
+      document.head.append(script);
+    });
+    return loading;
   }
-};
+
+  document$.subscribe(() => {
+    const currentRevision = ++revision;
+
+    // Serialize rendering and discard navigation events superseded during loading.
+    rendering = rendering.then(async () => {
+      if (currentRevision !== revision) {
+        return;
+      }
+      const content = document.querySelector(".md-content");
+      if (!content || !content.querySelector(".arithmatex")) {
+        if (loading) {
+          const mathjax = await loading;
+          mathjax.typesetClear();
+        }
+        return;
+      }
+
+      const mathjax = await loadMathJax();
+      if (currentRevision !== revision) {
+        return;
+      }
+      mathjax.startup.output.clearCache();
+      mathjax.typesetClear();
+      mathjax.texReset();
+      await mathjax.typesetPromise([content]);
+    }).catch(error => {
+      console.error("Jupiter Notes: unable to render mathematics.", error);
+    });
+  });
+})();