Title: PHP Error Log – Preg Match
Last modified: February 9, 2021

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# PHP Error Log – Preg Match

 *  Resolved [backpackingseries](https://wordpress.org/support/users/backpackingseries/)
 * (@backpackingseries)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/)
 * Hi,
 * Thanks for this really helpful plugin. Since the last update, there’s been a 
   string of records in the PHP error Log file
 *     ```
       [07-Feb-2021 04:26:58 UTC] PHP Warning:  preg_match(): Unknown modifier '/' in /wp-content/plugins/wp-asset-clean-up/classes/OptimiseAssets/CombineCss.php on line 394
       [07-Feb-2021 04:26:58 UTC] PHP Warning:  preg_match(): Unknown modifier '/' in /wp-content/plugins/wp-asset-clean-up/classes/OptimiseAssets/CombineJs.php on line 557
       ```
   
 * Anything that I could do to fix this please?
 * Kind regards,

Viewing 11 replies - 1 through 11 (of 11 total)

 *  [John](https://wordpress.org/support/users/dsl225/)
 * (@dsl225)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14023785)
 * Got exactly the same today (both).
 *  [felipelungov](https://wordpress.org/support/users/felipelungov/)
 * (@felipelungov)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14025440)
 * same here
 *  Plugin Author [Gabe Livan](https://wordpress.org/support/users/gabelivan/)
 * (@gabelivan)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14026174)
 * [@felipelungov](https://wordpress.org/support/users/felipelungov/) [@dsl225](https://wordpress.org/support/users/dsl225/)
   [@backpackingseries](https://wordpress.org/support/users/backpackingseries/) 
   I’ve released the development version which has a fix to avoid that error, so
   please update the version you’re currently using.
 * Here’s how you can do it: [https://www.assetcleanup.com/docs/how-to-get-the-development-version-of-asset-cleanup/](https://www.assetcleanup.com/docs/how-to-get-the-development-version-of-asset-cleanup/)
 * Now, I strongly believe it was because you had something written in the textarea
   for the exclusion of files from being combined that wasn’t alright. Now, even
   if the regular expression was invalid (perhaps you meant to write a string that
   will match exactly), it shouldn’t generate the error as it’s frustrating indeed
   to have it logged-in all the time to the error_log file.
 * I have a request from you, can you please reply to this topic with the value 
   you have in the textarea for both of the following: “_Do not combine the CSS 
   files matching the patterns below (one per line):_” & “_Do not combine the JavaScript
   files matching the patterns below (one per line, see pattern examples below):_“.
   I would like to check what you’ve written here.
 *  [John](https://wordpress.org/support/users/dsl225/)
 * (@dsl225)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14028254)
 * Thanks Gabe,
 * In the CSS box I have this:
 * (.*?).min.css
    /plugins/wd-instagram-feed/(.*?).css /plugins/forminator/(.*?).
   css
 * and the JS has this:
 * (.*?).min.js
    /plugins/wd-instagram-feed/(.*?).js /themes/corporate-plus-pro/
   assets/ /plugins/forminator/ /plugins/google-language-translator/js/ /plugins/
   easy-accordion-free/
 *  [felipelungov](https://wordpress.org/support/users/felipelungov/)
 * (@felipelungov)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14030851)
 * Thanks for your reply [@gabelivan](https://wordpress.org/support/users/gabelivan/).
 * Here is what I have for CSS:
 * /plugins/wd-instagram-feed/(.*?).css
 * For JS:
 * /plugins/wd-instagram-feed/(.*?).js
 * I guess we found the culprit. I’m removing those lines for now as I’m not even
   using that plugin.
 *  Thread Starter [backpackingseries](https://wordpress.org/support/users/backpackingseries/)
 * (@backpackingseries)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14035456)
 * Thank you [@gabelivan](https://wordpress.org/support/users/gabelivan/)
 * On my site, the option/s for **CSS Files Minification and JavaScript Files Minification
   are disabled**. But in the respective **grayed out** boxes for CSS and JS, I 
   see the following default values:
 * > CSS: Do not minify the CSS files matching the patterns below (one per line):
 *     ```
       (.*?)\.min.css
       /plugins/wd-instagram-feed/(.*?).css
       ```
   
 * > JS: Do not minify the JavaScript files matching the patterns below (one per
 *  line):
 *     ```
       (.*?)\.min.js
       /plugins/wd-instagram-feed/(.*?).js
       ```
   
 * However, the following options are enabled and specify the assets as follows:
 * > Combine loaded CSS (Stylesheets) into fewer files
 * `/plugins/wd-instagram-feed/(.*?).css`
 * > Combine loaded JS (JavaScript) into fewer files
 * `/plugins/wd-instagram-feed/(.*?).js`
 * PS: Like others have mentioned, I too do not have the `wd-instagram-feed` plugin
   installed on my site.
 * Kind regards,
    -  This reply was modified 5 years, 3 months ago by [backpackingseries](https://wordpress.org/support/users/backpackingseries/).
    -  This reply was modified 5 years, 3 months ago by [backpackingseries](https://wordpress.org/support/users/backpackingseries/).
 *  [John](https://wordpress.org/support/users/dsl225/)
 * (@dsl225)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14035621)
 * Guys, the entry with “wd-instagram” is just an example that is inserted in those
   boxes by default by the plugin first install in order to display how those entries
   should be used.
 * It’s not an error and is not related to the current issue.
    You may leave this
   as it is.
 *  Plugin Author [Gabe Livan](https://wordpress.org/support/users/gabelivan/)
 * (@gabelivan)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14037742)
 * [@dsl225](https://wordpress.org/support/users/dsl225/) [@backpackingseries](https://wordpress.org/support/users/backpackingseries/)
   [@felipelungov](https://wordpress.org/support/users/felipelungov/) based on my
   tests, it looks like there’s a bug there because of double delimiters (#) used
   at some point, just as the error says it. So, the values you had there were okay.
   They would not trigger the error. Moreover, the default values for exclusion 
   related to “wd-instagram-feed” were there for a long time and so far they have
   been working fine.
 * So, I’ve updated the development version which has the fix. Please read how to
   get it here – [https://www.assetcleanup.com/docs/how-to-get-the-development-version-of-asset-cleanup/](https://www.assetcleanup.com/docs/how-to-get-the-development-version-of-asset-cleanup/)–
   and let me know if you’re still getting any errors reported after that. You shouldn’t!
 *  [John](https://wordpress.org/support/users/dsl225/)
 * (@dsl225)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14039062)
 * Many thanks!
 *  [felipelungov](https://wordpress.org/support/users/felipelungov/)
 * (@felipelungov)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14041996)
 * Thanks! Just uploaded the development version, will check on Monday if I’m still
   getting those warnings.
 *  [felipelungov](https://wordpress.org/support/users/felipelungov/)
 * (@felipelungov)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14051924)
 * No more warnings with the development version. Already updated to the newest 
   version that I see also includes this fix. Thanks [@gabelivan](https://wordpress.org/support/users/gabelivan/)!

Viewing 11 replies - 1 through 11 (of 11 total)

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 * 11 replies
 * 4 participants
 * Last reply from: [felipelungov](https://wordpress.org/support/users/felipelungov/)
 * Last activity: [5 years, 3 months ago](https://wordpress.org/support/topic/php-error-log-preg-match/#post-14051924)
 * Status: resolved