diff --git a/wp-admin/includes/post.php b/wp-admin/includes/post.php
index a73f28e134..5f420e7846 100644
--- a/wp-admin/includes/post.php
+++ b/wp-admin/includes/post.php
@@ -1230,7 +1230,7 @@ function _admin_notice_post_locked() {
 		?>
 		<div class="post-locked-message">
 		<div class="post-locked-avatar"><?php echo get_avatar( $user->ID, 64 ); ?></div>
-		<p><?php esc_html_e( sprintf( __( 'This content is currently locked. If you take over, %s will be blocked from continuing to edit.' ), $user->display_name ) ); ?></p>
+		<p class="currently-editing" tabindex="0"><?php esc_html_e( sprintf( __( 'This content is currently locked. If you take over, %s will be blocked from continuing to edit.' ), $user->display_name ) ); ?></p>
 		<p>
 		<a class="button" href="<?php echo esc_url( wp_get_referer() ); ?>"><?php _e('Go back'); ?></a>
 		<a class="button" href="<?php echo esc_url( $preview_link ); ?>"><?php _e('Preview'); ?></a>
@@ -1251,7 +1251,7 @@ function _admin_notice_post_locked() {
 		?>
 		<div class="post-taken-over">
 			<div class="post-locked-avatar"></div>
-			<p class="currently-editing"></p>
+			<p class="currently-editing" tabindex="0"></p>
 			<p><a class="button button-primary" href="<?php echo esc_url( admin_url('edit.php') ); ?>"><?php _e('Go to All Posts'); ?></a></p>
 		</div>
 		<?php
diff --git a/wp-admin/js/post.js b/wp-admin/js/post.js
index 86fe18cd99..70792fb547 100644
--- a/wp-admin/js/post.js
+++ b/wp-admin/js/post.js
@@ -265,6 +265,7 @@ $(document).on( 'heartbeat-send.refresh-lock', function( e, data ) {
 	data['wp-refresh-post-lock'] = send;
 });
 
+// Post locks: update the lock string or show the dialog if somebody has taken over editing
 $(document).on( 'heartbeat-tick.refresh-lock', function( e, data ) {
 	var received, wrap, avatar;
 
@@ -277,19 +278,17 @@ $(document).on( 'heartbeat-tick.refresh-lock', function( e, data ) {
 
 			if ( ! wrap.is(':visible') ) {
 				autosave();
-				wrap.find('p.currently-editing').text( received.lock_error.text );
-				
+
 				if ( received.lock_error.avatar_src ) {
 					avatar = $('<img class="avatar avatar-64 photo" width="64" height="64" />').attr( 'src', received.lock_error.avatar_src.replace(/&amp;/g, '&') );
 					wrap.find('div.post-locked-avatar').empty().append( avatar );
 				}
 
-				wrap.show();
+				wrap.show().find('p.currently-editing').text( received.lock_error.text ).focus();
 			}
+		} else if ( received.new_lock ) {
+			$('#active_post_lock').val( received.new_lock );
 		}
-
-		if ( received['new_lock'] )
-			$('#active_post_lock').val( received['new_lock'].replace(/[^0-9:]+/, '') );
 	}
 });
 
@@ -300,6 +299,9 @@ jQuery(document).ready( function($) {
 
 	postboxes.add_postbox_toggles(pagenow);
 
+	// Post locks: if the Post Locked dialog is shown, focus it.
+	$('#notification-dialog:visible').find('p.currently-editing').focus();
+
 	// multi-taxonomies
 	if ( $('#tagsdiv-post_tag').length ) {
 		tagBox.init();