FressRSS/app/views/entry/read.phtml

<?php
header('Content-Type: application/json; charset=UTF-8');

$url = array(
	'c' => Minz_Request::controllerName(),
	'a' => Minz_Request::actionName(),
	'params' => Minz_Request::fetchGET(),
);

$url['params']['is_read'] = Minz_Request::param('is_read', true) ? '0' : '1';

FreshRSS::loadStylesAndScripts();
echo json_encode(array(
		'url' => str_ireplace('&amp;', '&', Minz_Url::display($url)),
		'icon' => _i($url['params']['is_read'] === '1' ? 'unread' : 'read')
	));