YOURLS plugin: keep query string

plugin.php

<?php
/*
Plugin Name: Keep Query String
Description: Adds short URL query string, if any, to the long URL
Version: 0.1
Author: Ozh
*/

yourls_add_filter('redirect_location', 'ozh_kqs');

function ozh_kqs($url){
    if (yourls_is_GO()) {
        $url = yourls_add_query_arg($_GET, $url);
    }
    return $url;
}

// well I think that's it

I'm not sure what the consequences of this are, but I managed to avoid the double encoding by duplicating the yourls_add_query_arg() function and commenting out the line that performs the reencoding (the call to yourls_urlencode_deep()).

Here's the full version: https://gist.github.com/rinogo/345dcfb149f1020f501b262ff45035d2

Thank you so much for your code. That is what I need :)

@congthien I've released an updated version of the plugin: YOURLS Keep Query String