diff --git a/website/pages/index.html b/website/pages/index.html
index 774ba4df..08fcab31 100644
--- a/website/pages/index.html
+++ b/website/pages/index.html
@@ -162,6 +162,10 @@
             </select>
           </td>
         </tr>
+        <tr>
+          <td><label for="trust">trust</label></td>
+          <td><input type="checkbox" id="trust"/></td>
+        </tr>
       </table>
       <h4><label for="macros">macros</label></h4>
       <textarea id="macros" placeholder="JSON">
diff --git a/website/static/js/index.js b/website/static/js/index.js
index 12fdbd28..e0773820 100644
--- a/website/static/js/index.js
+++ b/website/static/js/index.js
@@ -48,10 +48,12 @@ window.WebFontConfig = {
     }
 
     var katexOptions = ["displayMode", "leqno", "fleqn", "throwOnError",
-        "errorColor", "strict", "macros"].map(function(id) {
+        "errorColor", "strict", "trust", "macros"].map(function(id) {
             var el = document.getElementById(id);
             if (el.type === "checkbox") {
-                if (typeof data[id] === "boolean") {
+                if (typeof data[id] === "boolean" && !(id === "trust" && data[id] &&
+                        // eslint-disable-next-line no-alert, max-len
+                        !confirm("Enable 'trust' setting? Don't enable if you don't trust the source."))) {
                     el.checked = data[id];
                 }
             } else if (data[id]) {