can't fetch post

after a little research – it is failing in:
singletons/introspector.php::get_current_post()

b/c the $_GET is empty…

why?
Are there any known plugin conflicts?

solution is adding this code to the beggining of index.php:

$question_pos = strpos($_SERVER['REQUEST_URI'], '?');
if ($question_pos !== false) {
        $question_pos++; // don't want the ?
        $query = substr($_SERVER['REQUEST_URI'], $question_pos);
        parse_str($query, $_GET);
}

source:
​https://thomashunter.name/blog/wordpress-get-variables-with-lighttpd/