Merge branch 'master' into feature/add-tutorials-to-pdf

Author: the-matrixneo

_includes/head.html

@@ -102,5 +102,32 @@
 <link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/instantsearch.min.css">
 <link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/instantsearch-theme-algolia.min.css">
 
+<!-- QR code for printed pages -->
+<script defer src="https://cdn.jsdelivr.net/npm/[email protected]/qrcode.min.js"></script>
+<script>
+  document.addEventListener("DOMContentLoaded", function () {
+    var qrDiv = document.createElement("div");
+    qrDiv.id = "print-qr-code";
+    var qr = qrcode(0, "M");
+    qr.addData("{{ page.url | replace: 'index.html', '' | absolute_url }}");
+    qr.make();
+    qrDiv.innerHTML = qr.createImgTag(3, 0);
+    document.body.appendChild(qrDiv);
+  });
+</script>
+<style>
+  #print-qr-code {
+    display: none;
+  }
+  @media print {
+    #print-qr-code {
+      display: block;
+      position: fixed;
+      top: 0;
+      right: 0;
+    }
+  }
+</style>
+
 <!-- Plausible Analytics -->
 <script async defer data-domain="precice.org" src="https://plausible.io/js/plausible.js"></script>