Add target="_blank" to all URLs in the post author bio

author-bio-target-blank.php

<?php
/*
Plugin Name: Author Bio Target Blank
Plugin URI: https://gist.github.com/2ndkauboy/7136933
Description: Add target="_blank" to all URLs in the post author bio
Version: 0.1
Author: Bernhard Kau
Author URI: http://kau-boys.de
*/
 
function get_the_author_description_add_target_blank( $content ) {
	return str_replace( '<a', '<a target="_blank"', $content );
}
add_filter( 'get_the_author_description', 'get_the_author_description_add_target_blank' );