Get info about owner and last modified by in WordPress

page_owner_and_modified.php

function tl_show_page_owner(){

	// uncomment the line below if you want to use this only on pages.
	// if (!is_page()) return;

	$page = get_queried_object();
	
	if (!($page instanceof WP_Post)){
		return;
	}
	
	//$mod_date = date('M d, Y \a\t g:s a', strtotime($page->post_modified));
	
	$mod_date = get_the_modified_date();
	
	$page_owner = $page->post_author;
	$page_owner = get_user_by('id', $page->post_author);
	
	$first_name = get_user_meta($page->post_author, 'first_name', true);
	$last_name = get_user_meta($page->post_author, 'last_name', true);	
	
	if (!$first_name && !$last_name){
		$first_name = $page_owner->user_nicename;
	}
	
	$owner = $first_name . ' ' . $last_name;
	
	// get the person who did the modifications
	
	$last_editor_id = get_post_meta($page->ID, '_edit_last', true);

	$last_editor = "deleted user";

	if ($last_editor_id){
		$last_editor_user = get_user_by('id', $last_editor_id);
		if ($last_editor_user){
			$first_name = get_user_meta($last_editor_id, 'first_name', true);
			$last_name = get_user_meta($last_editor_id, 'last_name', true);	

			if (!$first_name && !$last_name){
				$first_name = $last_editor_user->user_nicename;
			}
			$last_editor = $first_name . ' ' . $last_name;
		}
	}
	
	echo "<p class='entry-meta page-owner'>Page owned by <a href='mailto:{$page_owner->user_email}'>$owner</a>. Last modified on <span class='date'>$mod_date</span> by $last_editor.</p>";

	
}