templates/base: support opening nav items in new tab

README.md

@@ -56,6 +56,7 @@ header_nav = [
     { name = "#tags", url = "/tags" },
     { name = "+categories", url = "/categories" },
     { name = "@contexts", url = "/contexts" },
+    { name = "example", url = "http://example.com", new_tab=true },
 ]
 footer_nav = [
     { name = "< previous", url = "#" },

templates/base.html

@@ -98,7 +98,7 @@
                 {% if config.extra.header_nav %}
                 <nav>
                     {% for nav_item in config.extra.header_nav %}
-                    <a href="{{ nav_item.url | safe }}">{{ nav_item.name }}</a>
+                    <a href="{{ nav_item.url | safe }}" {% if nav_item.new_tab %}target="_blank" rel="noreferrer noopener"{% endif %}>{{ nav_item.name }}</a>
                     {% endfor %}
                 </nav>
                 {% endif %}
@@ -120,4 +120,4 @@
         </div>
     </body>
 </html>
-        
+