Don't run time conversion if Intl not available in browser. Also convert

thread death time in archived threads

boards/static/js/main.js

@@ -23,6 +23,7 b''
  for the JavaScript code in this page.
  */
 
+if (window.Intl) {
 var LOCALE = window.navigator.language;
 var FORMATTER = new Intl.DateTimeFormat(
     LOCALE,
@@ -31,6 +32,7 b' var FORMATTER = new Intl.DateTimeFormat('
         hour: 'numeric', minute: '2-digit', second: '2-digit'
     }
 );
+}
 
 /**
  * An email is a hidden file to prevent spam bots from posting. It has to be
@@ -53,6 +55,10 b' function highlightCode(node) {'
  * Translate timestamps to local ones for all <time> tags inside node.
  */
 function translate_time(node) {
+    if (window.Intl === null) {
+        return;
+    }
+
     var elements;
 
     if (node === null) {

boards/templates/boards/post.html

@@ -26,7 +26,7 b''
     {% endcomment %}
     {% if thread.archived %}
         {% if is_opening %}
-        — {{ thread.bump_time }}
+        — <time datetime="{{ thread.bump_time|date:'c' }}">{{ thread.bump_time|date:'r' }}</time>
         {% endif %}
     {% endif %}
     {% if is_opening and need_open_link %}