diff --git a/layouts/partials/header.html b/layouts/partials/header.html
index 44336e1f14..d0cf2ab781 100644
--- a/layouts/partials/header.html
+++ b/layouts/partials/header.html
@@ -126,7 +126,7 @@
             {{- $page_url:= $currentPage.Permalink | absLangURL }}
             {{- $is_search := eq (site.GetPage .KeyName).Layout `search` }}
             <li>
-                <a href="{{ .URL | absLangURL }}" title="{{ .Title | default .Name }} {{- cond $is_search (" (Alt + /)" | safeHTMLAttr) ("" | safeHTMLAttr ) }}"
+                <a href="{{ .URL | absLangURL }}" {{- if (hasPrefix .Identifier "ext-") }} target="_blank" {{- end }} title="{{ .Title | default .Name }} {{- cond $is_search (" (Alt + /)" | safeHTMLAttr) ("" | safeHTMLAttr ) }}"
                 {{- cond $is_search (" accesskey=/" | safeHTMLAttr) ("" | safeHTMLAttr ) }}>
                     <span {{- if eq $menu_item_url $page_url }} class="active" {{- end }}>
                         {{- .Pre }}