head.html: handle null header_td_form on homepage

Fixes:

Uncaught TypeError: header_td_form is null

1 files changed, 5 insertions, 3 deletions

diff --git a/head.html b/head.html
index 7ee78be..3796203 100644
--- a/head.html
+++ b/head.html
@@ -16,10 +16,12 @@
     tabs.className = "tabs";
     forms.className = "forms";
     var header_td_form = document.querySelector("table#header td.form");
-    while (header_td_form.firstChild) {
-      header_form.appendChild(header_td_form.firstChild);
+    if (header_td_form) {
+      while (header_td_form.firstChild) {
+        header_form.appendChild(header_td_form.firstChild);
+      }
+      header_td_form.parentNode.removeChild(header_td_form);
     }
-    header_td_form.parentNode.removeChild(header_td_form);
     var tab_items = Array.from(document.querySelectorAll("table.tabs td")).map(
       (v) => {
         var div = document.createElement("div");