diff --git a/phpBB/includes/functions_display.php b/phpBB/includes/functions_display.php
index ea5ff08c01..a49a594ade 100644
--- a/phpBB/includes/functions_display.php
+++ b/phpBB/includes/functions_display.php
@@ -650,6 +650,8 @@ function generate_forum_nav(&$forum_data)
 	// Get forum parents
 	$forum_parents = get_forum_parents($forum_data);
 
+	$microdata_attr = 'data-forum-id';
+
 	// Build navigation links
 	if (!empty($forum_parents))
 	{
@@ -669,6 +671,7 @@ function generate_forum_nav(&$forum_data)
 				'S_IS_POST'		=> ($parent_type == FORUM_POST) ? true : false,
 				'FORUM_NAME'	=> $parent_name,
 				'FORUM_ID'		=> $parent_forum_id,
+				'MICRODATA'		=> $microdata_attr . '="' . $parent_forum_id . '"',
 				'U_VIEW_FORUM'	=> append_sid("{$phpbb_root_path}viewforum.$phpEx", 'f=' . $parent_forum_id))
 			);
 		}
@@ -680,6 +683,7 @@ function generate_forum_nav(&$forum_data)
 		'S_IS_POST'		=> ($forum_data['forum_type'] == FORUM_POST) ? true : false,
 		'FORUM_NAME'	=> $forum_data['forum_name'],
 		'FORUM_ID'		=> $forum_data['forum_id'],
+		'MICRODATA'		=> $microdata_attr . '="' . $forum_data['forum_id'] . '"',
 		'U_VIEW_FORUM'	=> append_sid("{$phpbb_root_path}viewforum.$phpEx", 'f=' . $forum_data['forum_id']))
 	);
 
diff --git a/phpBB/styles/prosilver/template/navbar_header.html b/phpBB/styles/prosilver/template/navbar_header.html
index 092a268b0f..e1875809bc 100644
--- a/phpBB/styles/prosilver/template/navbar_header.html
+++ b/phpBB/styles/prosilver/template/navbar_header.html
@@ -8,7 +8,7 @@
 			<span class="crumb"><a href="{U_INDEX}" accesskey="h"{$MICRODATA} data-navbar-reference="index">{L_INDEX}</a></span>
 			<!-- BEGIN navlinks -->
 				<!-- EVENT overall_header_navlink_prepend -->
-				<span class="crumb"><a href="{navlinks.U_VIEW_FORUM}"{$MICRODATA}<!-- IF navlinks.FORUM_ID --> data-forum-id="{navlinks.FORUM_ID}"<!-- ENDIF -->>{navlinks.FORUM_NAME}</a></span>
+				<span class="crumb"><a href="{navlinks.U_VIEW_FORUM}"{$MICRODATA}<!-- IF navlinks.MICRODATA --> {navlinks.MICRODATA}<!-- ENDIF -->>{navlinks.FORUM_NAME}</a></span>
 				<!-- EVENT overall_header_navlink_append -->
 			<!-- END navlinks -->
 			<!-- EVENT overall_header_breadcrumb_append -->
diff --git a/phpBB/styles/subsilver2/template/breadcrumbs.html b/phpBB/styles/subsilver2/template/breadcrumbs.html
index 667875be4a..3aa05bc0eb 100644
--- a/phpBB/styles/subsilver2/template/breadcrumbs.html
+++ b/phpBB/styles/subsilver2/template/breadcrumbs.html
@@ -2,7 +2,7 @@
 	<table class="tablebg" width="100%" cellspacing="1" cellpadding="0" style="margin-top: 5px;">
 	<tr>
 		<td class="row1">
-			<p class="breadcrumbs"><!-- IF U_SITE_HOME --><a href="{U_SITE_HOME}"{$MICRODATA} data-navbar-reference="home">{L_SITE_HOME}</a> <strong>&#187;</strong> <!-- ENDIF --><a href="{U_INDEX}"{$MICRODATA} data-navbar-reference="index">{L_INDEX}</a><!-- BEGIN navlinks --><!-- EVENT overall_header_navlink_prepend --> &#187; <a href="{navlinks.U_VIEW_FORUM}"{$MICRODATA}<!-- IF navlinks.FORUM_ID --> data-forum-id="{navlinks.FORUM_ID}"<!-- ENDIF -->>{navlinks.FORUM_NAME}</a><!-- EVENT overall_header_navlink_append --><!-- END navlinks -->
+			<p class="breadcrumbs"><!-- IF U_SITE_HOME --><a href="{U_SITE_HOME}"{$MICRODATA} data-navbar-reference="home">{L_SITE_HOME}</a> <strong>&#187;</strong> <!-- ENDIF --><a href="{U_INDEX}"{$MICRODATA} data-navbar-reference="index">{L_INDEX}</a><!-- BEGIN navlinks --><!-- EVENT overall_header_navlink_prepend --> &#187; <a href="{navlinks.U_VIEW_FORUM}"{$MICRODATA}<!-- IF navlinks.MICRODATA --> {navlinks.MICRODATA}<!-- ENDIF -->>{navlinks.FORUM_NAME}</a><!-- EVENT overall_header_navlink_append --><!-- END navlinks -->
 			<!-- EVENT overall_header_breadcrumb_append --></p>
 			<!-- EVENT overall_footer_timezone_before -->
 			<p class="datetime">{S_TIMEZONE}</p>