$re = '/s=\'(?<img>[^\']+)\';\w+\s\w+=\[\'(?<id>\w+_\d+)\'];/m';
$str = '<script nonce="cRlsgv0sADvnNakDIZj-4w">(function(){var s=\'data:image/png;base64,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\\x3d\';var ii=[\'wp_thbn_66\'];_setImagesSrc(ii,s);})();</script>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php