diff --git a/tests/phpunit/tests/general/feedLinksExtra.php b/tests/phpunit/tests/general/feedLinksExtra.php
new file mode 100644
index 0000000000..c885cac88c
--- /dev/null
+++ b/tests/phpunit/tests/general/feedLinksExtra.php
@@ -0,0 +1,513 @@
+<?php
+/**
+ * Test feed_links_extra().
+ *
+ * @ticket 54713
+ *
+ * @group general
+ * @group template
+ *
+ * @covers ::feed_links_extra
+ */
+class Tests_General_FeedLinksExtra extends WP_UnitTestCase {
+	/**
+	 * Author ID.
+	 *
+	 * @var int
+	 */
+	protected static $author_id;
+
+	/**
+	 * Category ID.
+	 *
+	 * @var int
+	 */
+	protected static $category_id;
+
+	/**
+	 * Tag ID.
+	 *
+	 * @var int
+	 */
+	protected static $tag_id;
+
+	/**
+	 * Taxonomy ID.
+	 *
+	 * @var int
+	 */
+	protected static $tax_id;
+
+	/**
+	 * Post Type.
+	 *
+	 * @var string
+	 */
+	protected static $post_type;
+
+	/**
+	 * The ID of a post with no comment.
+	 *
+	 * @var int
+	 */
+	protected static $post_no_comment_id;
+
+	/**
+	 * The ID of a post with a comment.
+	 *
+	 * @var int
+	 */
+	protected static $post_with_comment_id;
+
+	/**
+	 * The ID of a post with a custom post type.
+	 *
+	 * @var int
+	 */
+	protected static $post_with_cpt_id;
+
+	public static function wpSetUpBeforeClass( WP_UnitTest_Factory $factory ) {
+		// Author.
+		self::$author_id = $factory->user->create(
+			array(
+				'user_login' => 'author_feed_links_extra',
+				'role'       => 'administrator',
+			)
+		);
+
+		// Category.
+		self::$category_id = $factory->category->create(
+			array( 'name' => 'cat_feed_links_extra' )
+		);
+
+		// Tag.
+		self::$tag_id = $factory->tag->create(
+			array( 'name' => 'tag_feed_links_extra' )
+		);
+
+		// Taxonomy.
+		self::$tax_id = 'tax_feed_links_extra';
+
+		// Post type.
+		self::$post_type = 'cpt_feed_links_extra';
+
+		register_taxonomy(
+			self::$tax_id,
+			self::$post_type,
+			array(
+				'labels' => array(
+					'name'          => 'Taxonomy Terms',
+					'singular_name' => 'Taxonomy Term',
+				),
+			)
+		);
+
+		register_post_type(
+			self::$post_type,
+			array(
+				'public'      => true,
+				'has_archive' => true,
+				'taxonomies'  => array( self::$tax_id ),
+				'labels'      => array( 'name' => 'CPT for feed_links_extra()' ),
+			)
+		);
+
+		// Posts.
+		self::$post_no_comment_id = $factory->post->create(
+			array( 'post_title' => 'Post with no comments' )
+		);
+
+		self::$post_with_comment_id = $factory->post->create(
+			array( 'post_title' => 'Post with a comment' )
+		);
+
+		$factory->comment->create(
+			array(
+				'comment_author'  => self::$author_id,
+				'comment_post_ID' => self::$post_with_comment_id,
+			)
+		);
+
+		self::$post_with_cpt_id = $factory->post->create(
+			array(
+				'post_title' => 'Post with a custom post type',
+				'post_type'  => self::$post_type,
+			)
+		);
+
+		wp_set_object_terms( self::$post_with_cpt_id, 'tax_term', self::$tax_id );
+	}
+
+	public function set_up() {
+		parent::set_up();
+
+		register_taxonomy(
+			self::$tax_id,
+			self::$post_type,
+			array(
+				'labels' => array(
+					'name'          => 'Taxonomy Terms',
+					'singular_name' => 'Taxonomy Term',
+				),
+			)
+		);
+
+		register_post_type(
+			self::$post_type,
+			array(
+				'public'      => true,
+				'has_archive' => true,
+				'taxonomies'  => array( self::$tax_id ),
+				'labels'      => array( 'name' => 'CPT for feed_links_extra()' ),
+			)
+		);
+	}
+
+	/**
+	 * @dataProvider data_feed_links_extra
+	 * @ticket 54713
+	 *
+	 * @param string $title     The expected title.
+	 * @param string $type      The name of the test class property containing the object ID.
+	 * @param array  $args {
+	 *        Optional arguments. Default empty.
+	 *
+	 *        @type string $separator     The separator between blog name and feed type.
+	 *        @type string $singletitle   The title of the comments feed.
+	 *        @type string $cattitle      The title of the category feed.
+	 *        @type string $tagtitle      The title of the tag feed.
+	 *        @type string $taxtitle      The title of the taxonomy feed.
+	 *        @type string $authortitle   The title of the author feed.
+	 *        @type string $searchtitle   The title of the search feed.
+	 *        @type string $posttypetitle The title of the post type feed.
+	 * }
+	 */
+	public function test_feed_links_extra( $title, $type, array $args = array() ) {
+		$permalink = $this->helper_get_the_permalink( $type );
+		$this->go_to( $permalink );
+
+		$expected = '';
+
+		if ( '' !== $title ) {
+			if ( 'post_type' === $type || 'search' === $type ) {
+				$feed_link = $permalink . '&#038;feed=rss2';
+			} else {
+				$feed_link = str_replace( '?', '?feed=rss2&#038;', $permalink );
+			}
+
+			$expected = sprintf(
+				'<link rel="alternate" type="application/rss+xml" title="%s" href="%s" />' . "\n",
+				esc_attr( $title ),
+				esc_url( $feed_link )
+			);
+		}
+
+		$this->assertSame( $expected, get_echo( 'feed_links_extra', array( $args ) ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_feed_links_extra() {
+		return array(
+			'a post with a comment'                        => array(
+				'title' => 'Test Blog &raquo; Post with a comment Comments Feed',
+				'type'  => 'post_with_comment',
+			),
+			'a post with a comment and a custom separator' => array(
+				'title' => 'Test Blog // Post with a comment Comments Feed',
+				'type'  => 'post_with_comment',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'a post with a comment and a custom title'     => array(
+				'title' => 'Custom Title for Singular Feed',
+				'type'  => 'post_with_comment',
+				'args'  => array(
+					'singletitle' => 'Custom Title for Singular Feed',
+				),
+			),
+			'a post with a comment, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Singular Feed',
+				'type'  => 'post_with_comment',
+				'args'  => array(
+					'separator'   => '//',
+					'singletitle' => '%1$s %2$s Custom Title for Singular Feed',
+				),
+			),
+			'a custom post type'                           => array(
+				'title' => 'Test Blog &raquo; CPT for feed_links_extra() Feed',
+				'type'  => 'post_type',
+			),
+			'a custom post type and a custom separator'    => array(
+				'title' => 'Test Blog // CPT for feed_links_extra() Feed',
+				'type'  => 'post_type',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'a custom post type and a custom title'        => array(
+				'title' => 'Custom Title for CPT Feed',
+				'type'  => 'post_type',
+				'args'  => array(
+					'posttypetitle' => 'Custom Title for CPT Feed',
+				),
+			),
+			'a custom post type, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for CPT Feed',
+				'type'  => 'post_type',
+				'args'  => array(
+					'separator'     => '//',
+					'posttypetitle' => '%1$s %2$s Custom Title for CPT Feed',
+				),
+			),
+			'a category'                                   => array(
+				'title' => 'Test Blog &raquo; cat_feed_links_extra Category Feed',
+				'type'  => 'category',
+			),
+			'a category and a custom separator'            => array(
+				'title' => 'Test Blog // cat_feed_links_extra Category Feed',
+				'type'  => 'category',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'a category and a custom title'                => array(
+				'title' => 'Custom Title for Category Feed',
+				'type'  => 'category',
+				'args'  => array(
+					'cattitle' => 'Custom Title for Category Feed',
+				),
+			),
+			'a category, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Category Feed',
+				'type'  => 'category',
+				'args'  => array(
+					'separator' => '//',
+					'cattitle'  => '%1$s %2$s Custom Title for Category Feed',
+				),
+			),
+			'a tag'                                        => array(
+				'title' => 'Test Blog &raquo; tag_feed_links_extra Tag Feed',
+				'type'  => 'tag',
+			),
+			'a tag and a custom separator'                 => array(
+				'title' => 'Test Blog // tag_feed_links_extra Tag Feed',
+				'type'  => 'tag',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'a tag and a custom title'                     => array(
+				'title' => 'Custom Title for Tag Feed',
+				'type'  => 'tag',
+				'args'  => array(
+					'tagtitle' => 'Custom Title for Tag Feed',
+				),
+			),
+			'a tag, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Tag Feed',
+				'type'  => 'tag',
+				'args'  => array(
+					'separator' => '//',
+					'tagtitle'  => '%1$s %2$s Custom Title for Tag Feed',
+				),
+			),
+			'a taxonomy'                                   => array(
+				'title' => 'Test Blog &raquo; tax_term Taxonomy Term Feed',
+				'type'  => 'tax',
+			),
+			'a taxonomy and a custom separator'            => array(
+				'title' => 'Test Blog // tax_term Taxonomy Term Feed',
+				'type'  => 'tax',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'a taxonomy and a custom title'                => array(
+				'title' => 'Custom Title for Taxonomy Feed',
+				'type'  => 'tax',
+				'args'  => array(
+					'taxtitle' => 'Custom Title for Taxonomy Feed',
+				),
+			),
+			'a taxonomy, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Taxonomy Feed',
+				'type'  => 'tax',
+				'args'  => array(
+					'separator' => '//',
+					'taxtitle'  => '%1$s %2$s Custom Title for Taxonomy Feed',
+				),
+			),
+			'an author'                                    => array(
+				'title' => 'Test Blog &raquo; Posts by author_feed_links_extra Feed',
+				'type'  => 'author',
+			),
+			'an author and a custom separator'             => array(
+				'title' => 'Test Blog // Posts by author_feed_links_extra Feed',
+				'type'  => 'author',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'an author and a custom title'                 => array(
+				'title' => 'Custom Title for Author Feed',
+				'type'  => 'author',
+				'args'  => array(
+					'authortitle' => 'Custom Title for Author Feed',
+				),
+			),
+			'an author, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Author Feed',
+				'type'  => 'author',
+				'args'  => array(
+					'separator'   => '//',
+					'authortitle' => '%1$s %2$s Custom Title for Author Feed',
+				),
+			),
+			'search results'                               => array(
+				'title' => 'Test Blog &raquo; Search Results for &#8220;Search&#8221; Feed',
+				'type'  => 'search',
+			),
+			'search results and a custom separator'        => array(
+				'title' => 'Test Blog // Search Results for &#8220;Search&#8221; Feed',
+				'type'  => 'search',
+				'args'  => array(
+					'separator' => '//',
+				),
+			),
+			'search results and a custom title'            => array(
+				'title' => 'Custom Title for Search Feed',
+				'type'  => 'search',
+				'args'  => array(
+					'searchtitle' => 'Custom Title for Search Feed',
+				),
+			),
+			'search results, a custom separator and a custom title' => array(
+				'title' => 'Test Blog // Custom Title for Search Feed',
+				'type'  => 'search',
+				'args'  => array(
+					'separator'   => '//',
+					'searchtitle' => '%1$s %2$s Custom Title for Search Feed',
+				),
+			),
+		);
+	}
+
+	/**
+	 * Helper function to get the permalink based on type.
+	 *
+	 * @ticket 54713
+	 *
+	 * @param string $type The name of the test class property containing the object ID.
+	 * @return string The permalink.
+	 */
+	private function helper_get_the_permalink( $type ) {
+		if ( 'category' === $type || 'tag' === $type ) {
+			return get_term_link( self::${$type . '_id'} );
+		}
+
+		if ( 'tax' === $type ) {
+			return get_term_link( 'tax_term', self::$tax_id );
+		}
+
+		if ( 'post_type' === $type ) {
+			return get_post_type_archive_link( self::$post_type );
+		}
+
+		if ( 'author' === $type ) {
+			return get_author_posts_url( self::$author_id );
+		}
+
+		if ( 'search' === $type ) {
+			return home_url( '?s=Search' );
+		}
+
+		return get_the_permalink( self::${$type . '_id'} );
+	}
+
+	/**
+	 * @ticket 54713
+	 */
+	public function test_feed_links_extra_should_respect_comments_open() {
+		add_filter( 'comments_open', '__return_true' );
+		add_filter( 'pings_open', '__return_false' );
+
+		$this->go_to( get_the_permalink( self::$post_no_comment_id ) );
+
+		$expected  = '<link rel="alternate" type="application/rss+xml"';
+		$expected .= ' title="Test Blog &raquo; Post with no comments Comments Feed"';
+		$expected .= ' href="http://example.org/?feed=rss2&#038;p=' . self::$post_no_comment_id . '" />' . "\n";
+		$this->assertSame( $expected, get_echo( 'feed_links_extra' ) );
+	}
+
+	/**
+	 * @ticket 54713
+	 */
+	public function test_feed_links_extra_should_respect_pings_open() {
+		add_filter( 'pings_open', '__return_true' );
+		add_filter( 'comments_open', '__return_false' );
+
+		$this->go_to( get_the_permalink( self::$post_no_comment_id ) );
+
+		$expected  = '<link rel="alternate" type="application/rss+xml"';
+		$expected .= ' title="Test Blog &raquo; Post with no comments Comments Feed"';
+		$expected .= ' href="http://example.org/?feed=rss2&#038;p=' . self::$post_no_comment_id . '" />' . "\n";
+		$this->assertSame( $expected, get_echo( 'feed_links_extra' ) );
+	}
+
+	/**
+	 * @ticket 54713
+	 */
+	public function test_feed_links_extra_should_respect_post_comment_count() {
+		add_filter( 'pings_open', '__return_false' );
+		add_filter( 'comments_open', '__return_false' );
+
+		$this->go_to( get_the_permalink( self::$post_with_comment_id ) );
+
+		$expected  = '<link rel="alternate" type="application/rss+xml"';
+		$expected .= ' title="Test Blog &raquo; Post with a comment Comments Feed"';
+		$expected .= ' href="http://example.org/?feed=rss2&#038;p=' . self::$post_with_comment_id . '" />' . "\n";
+		$this->assertSame( $expected, get_echo( 'feed_links_extra' ) );
+	}
+
+	/**
+	 * @ticket 54713
+	 */
+	public function test_feed_links_extra_should_return_empty_when_comments_and_pings_are_closed_and_post_has_no_comments() {
+		add_filter( 'comments_open', '__return_false' );
+		add_filter( 'pings_open', '__return_false' );
+
+		$this->go_to( get_the_permalink( self::$post_no_comment_id ) );
+		$this->assertEmpty( get_echo( 'feed_links_extra' ) );
+	}
+
+	/**
+	 * @ticket 54713
+	 */
+	public function test_feed_links_extra_should_respect_feed_type() {
+		add_filter(
+			'default_feed',
+			static function() {
+				return 'foo';
+			}
+		);
+
+		add_filter(
+			'feed_content_type',
+			static function() {
+				return 'testing/foo';
+			}
+		);
+
+		$this->go_to( get_the_permalink( self::$post_with_comment_id ) );
+
+		$expected  = '<link rel="alternate" type="testing/foo"';
+		$expected .= ' title="Test Blog &raquo; Post with a comment Comments Feed"';
+		$expected .= ' href="http://example.org/?feed=foo&#038;p=' . self::$post_with_comment_id . '" />' . "\n";
+		$this->assertSame( $expected, get_echo( 'feed_links_extra' ) );
+	}
+}