Title: problem with cssmgr.php in apache error.log
Last modified: March 7, 2017

---

# problem with cssmgr.php in apache error.log

 *  Resolved [mahi38](https://wordpress.org/support/users/mahi38/)
 * (@mahi38)
 * [9 years, 3 months ago](https://wordpress.org/support/topic/problem-with-cssmgr-php-in-apache-error-log/)
 * Hello,
    Thanks for this great plugin ! I get the following endless warnings in
   the Apache error.log when generating invoices – does anybody know how to fix 
   the issue ? thanks a lot
 *     ```
       [07-Mar-2017 15:18:39 UTC] PHP Warning:  Illegal string offset 'ID' in /home/arkanova/public_html/wp_33/wp-content/plugins/woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php on line 1302
       [07-Mar-2017 15:18:39 UTC] PHP Warning:  Cannot assign an empty string to a string offset in /home/arkanova/public_html/wp_33/wp-content/plugins/woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php on line 1302
       [07-Mar-2017 15:18:39 UTC] PHP Warning:  Illegal string offset 'LANG' in /home/arkanova/public_html/wp_33/wp-content/plugins/woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php on line 1307
       [07-Mar-2017 15:18:39 UTC] PHP Warning:  Cannot assign an empty string to a string offset in /home/arkanova/public_html/wp_33/wp-content/plugins/woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php on line 1307
       [07-Mar-2017 15:18:39 UTC] PHP Warning:  Illegal string offset 'ID' in /home/arkanova/public_html/wp_33/wp-content/plugins/woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php on line 1355
       ```
   

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Thread Starter [mahi38](https://wordpress.org/support/users/mahi38/)
 * (@mahi38)
 * [9 years, 3 months ago](https://wordpress.org/support/topic/problem-with-cssmgr-php-in-apache-error-log/#post-8896557)
 * OK – I understand function MergeCSS() is called in mpdf.php with $attr being ”,
   so statements like :
    – $attr[‘ID’] = ”; // line 1302 in cssmgr.php – $attr[‘
   LANG’] = ”; // line 1307 are generating warnings _Cannot assign an empty string
   to a string offset…_ in PHP 7.1.2
 * I fixed the problem in adding the following 3 lines in :
    – **file **: plugins/
   woocommerce-pdf-invoices/lib/mpdf/classes/cssmgr.php – **function **: MergeCSS(
   $inherit, $tag, $attr) – **after **: $zp = array(); // line 1295
 *     ```
       if (! is_array($attr)) {
           $attr = array();
       }
       ```
   
 * If this is the correct code to solve the problem it would be nice to have the
   fix integrated in the next release.
 * The plugin is great – let’s keep up with the good work.
 * cheers
 *  Plugin Author [Bas Elbers](https://wordpress.org/support/users/baaaaas/)
 * (@baaaaas)
 * [9 years, 2 months ago](https://wordpress.org/support/topic/problem-with-cssmgr-php-in-apache-error-log/#post-8921344)
 * I am aware of this issue. It is related to PHP 7.1. Will update plugin as soon
   as possible.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘problem with cssmgr.php in apache error.log’ is closed to new replies.

 * ![](https://ps.w.org/woocommerce-pdf-invoices/assets/icon-128x128.png?rev=1128583)
 * [Invoices for WooCommerce](https://wordpress.org/plugins/woocommerce-pdf-invoices/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/woocommerce-pdf-invoices/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/woocommerce-pdf-invoices/)
 * [Active Topics](https://wordpress.org/support/plugin/woocommerce-pdf-invoices/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/woocommerce-pdf-invoices/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/woocommerce-pdf-invoices/reviews/)

 * 2 replies
 * 2 participants
 * Last reply from: [Bas Elbers](https://wordpress.org/support/users/baaaaas/)
 * Last activity: [9 years, 2 months ago](https://wordpress.org/support/topic/problem-with-cssmgr-php-in-apache-error-log/#post-8921344)
 * Status: resolved