Index: src/wp-admin/plugins.php
===================================================================
--- src/wp-admin/plugins.php	(revision 28959)
+++ src/wp-admin/plugins.php	(working copy)
@@ -415,8 +415,11 @@
 if ( ( ! is_multisite() || is_network_admin() ) && current_user_can('install_plugins') ) { ?>
  <a href="<?php echo self_admin_url( 'plugin-install.php' ); ?>" class="add-new-h2"><?php echo esc_html_x('Add New', 'plugin'); ?></a>
 <?php }
-if ( $s )
-	printf( '<span class="subtitle">' . __('Search results for &#8220;%s&#8221;') . '</span>', esc_html( $s ) ); ?>
+$s = trim( $s );
+if ( ! empty( $s ) ) {
+	printf( '<span class="subtitle">' . __('Search results for &#8220;%s&#8221;') . '</span>', esc_html( $s ) ); 
+} 
+?>
 </h2>
 
 <?php