Title: Forminator Fatal PHP error
Last modified: October 28, 2025

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# Forminator Fatal PHP error

 *  Resolved [buschwichtel](https://wordpress.org/support/users/buschwichtel/)
 * (@buschwichtel)
 * [7 months, 1 week ago](https://wordpress.org/support/topic/forminator-fatal-php-error/)
 * Activating Forminator breaks our website with the attached server log.
 * We use a total of two forms, neither of which appear to use the cross sell submenu(
   I am uncertain of how to check, but cross-selling is at the very least not a 
   functionality that we require.)
 * Disabling the forminator plugin restores functionality to the web page in the
   short term, but is of course not an acceptable long-term solution.
 * Do you have any ideas what might be causing this error?
 * Best regards
 *     ```wp-block-code
       [28-Oct-2025 17:07:49 UTC] PHP Fatal error: Uncaught TypeError: WPMUDEV\Modules\Plugin_Cross_Sell\App\Submenus\CrossSell::init(): Argument #1 ($container) must be of type WPMUDEV\Modules\Plugin_Cross_Sell\Container, WPMUDEV\Modules\Plugin_Cross_Sell\Container given, called in /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/core/class-loader.php on line 108 and defined in /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/app/submenus/class-cross-sell.php:99Stack trace: 0 /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/core/class-loader.php(108): WPMUDEV\Modules\Plugin_Cross_Sell\App\Submenus\CrossSell->init() 1 /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/core/class-loader.php(76): WPMUDEV\Modules\Plugin_Cross_Sell\Loader->setup_components() 2 /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/plugin-cross-sell.php(103): WPMUDEV\Modules\Plugin_Cross_Sell\Loader->init() 3 /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/plugin-cross-sell.php(85): WPMUDEV\Modules\Plugin_Cross_Sell->load() 4 /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/class-core.php(438): WPMUDEV\Modules\Plugin_Cross_Sell->__construct() 5 /homepages/30/d4297102870/htdocs/wordpress/wp-includes/class-wp-hook.php(324): Forminator_Core::load_cross_sell_module() 6 /homepages/30/d4297102870/htdocs/wordpress/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() 7 /homepages/30/d4297102870/htdocs/wordpress/wp-includes/plugin.php(517): WP_Hook->do_action() 8 /homepages/30/d4297102870/htdocs/wordpress/wp-settings.php(727): do_action() 9 /homepages/30/d4297102870/htdocs/wordpress/wp-config.php(197): require_once('/homepages/30/d…') 10 /homepages/30/d4297102870/htdocs/wordpress/wp-load.php(50): require_once('/homepages/30/d…') 11 /homepages/30/d4297102870/htdocs/wordpress/wp-blog-header.php(13): require_once('/homepages/30/d…') 12 /homepages/30/d4297102870/htdocs/wordpress/index.php(17): require('/homepages/30/d…') 13 {main}thrown in /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/library/lib/plugins-cross-sell-page/app/submenus/class-cross-sell.php on line 99
       ```
   

Viewing 7 replies - 1 through 7 (of 7 total)

 *  Plugin Support [Saurabh – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support7/)
 * (@wpmudev-support7)
 * [7 months, 1 week ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18699323)
 * Hello [@buschwichtel](https://wordpress.org/support/users/buschwichtel/) ,
 * I am sorry to hear about the issue you’re facing. I tried to replicate the issue
   on my lab environment with the latest version of Forminator, v1.48.2, with the
   server running PHP 8.2.3. However, I was not able to replicate the fatal error.
 * The Plugin_Cross_Sell module is a part of the Forminator Plugin code and is not
   related to any cross-selling functionality on your website. However, could you
   please confirm if you are using the latest version of the Forminator plugin and
   also share with us the PHP Version you are using? Further, can you please confirm
   if you already tried reinstalling the plugin?
 * Additionally, I have also informed the Forminator team about the error to gain
   additional insights from them about the error. We will keep you posted as soon
   as we receive further updates from them.
 * Kind Regards,
    Saurabh
 *  Thread Starter [buschwichtel](https://wordpress.org/support/users/buschwichtel/)
 * (@buschwichtel)
 * [7 months, 1 week ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18699492)
 * Hello [@wpmudev-support7](https://wordpress.org/support/users/wpmudev-support7/),
 * thank you for the response.
 * This is on PHP 8.1.33. The plugin is up to date (so on 1.48.2.)
 * Is a full reinstall of the plugin possible without losing forminator configuration
   data etc.?
 * Best Regards
 *  Plugin Support [Nebu John – WPMU DEV Support](https://wordpress.org/support/users/wpmudevsupport14/)
 * (@wpmudevsupport14)
 * [7 months, 1 week ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18700695)
 * Hi [@buschwichtel](https://wordpress.org/support/users/buschwichtel/),
 * To check the issue further, I tried to replicate the issue on my lab environment
   with PHP version 8.1, but I still wasn’t able to replicate the issue. This suggests
   the issue is specific to your website.
 * > Is a full reinstall of the plugin possible without losing forminator configuration
   > data etc.?
 * Forminator provides an option to preserve the data in the database on uninstallation.
   You can find the same at Forminator >> Settings >> Data. Please find more about
   the same in our documentation here: [https://wpmudev.com/docs/wpmu-dev-plugins/forminator/#uninstallation](https://wpmudev.com/docs/wpmu-dev-plugins/forminator/#uninstallation)
 * Alternatively, you can try replacing the plugin files using FTP/cPanel File Manager.
 * Please try reinstalling the plugin and check if that helps to resolve the issue.
 * Best Regards,
    Nebu John
 *  Plugin Support [Saurabh – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support7/)
 * (@wpmudev-support7)
 * [7 months, 1 week ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18700726)
 * Hello [@buschwichtel](https://wordpress.org/support/users/buschwichtel/)
 * An update here from the Forminator team,
 * There is a possibility that the Fatal error happening could be due to another
   WPMU DEV plugin that could be outdated. In this case, to fully narrow down the
   issue, it is recommended that you carry out a full plugin conflict test by disabling
   all the active plugins on your site and then activating Forminator and checking
   if the fatal error occurs. If it works as expected, please activate each plugin
   at a time until you replicate the issue. This will help you narrow down the plugin
   that could be conflicting.
 * Since the test involves activating and deactivating plugins, if this is a live
   site, I would recommend that you create a staging site and perform the test there.
   In case a staging is not possible, please ensure you take a full backup of the
   live site before doing the conflict test.
 * Additionally, if there are plugin or WP Core updates pending, please secure a
   full backup and perform the updates to see if that resolves the issue.
 * Please do let us know how it goes. We’ll be more than happy to help you further.
 * Kind Regards,
    Saurabh
 *  Plugin Support [Amin – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support2/)
 * (@wpmudev-support2)
 * [7 months ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18713498)
 * Hello [@buschwichtel](https://wordpress.org/support/users/buschwichtel/)
 * We haven’t heard from you in some time, so I will mark this thread as resolved.
   If you have any more questions or need further assistance, please let us know!
 * Kind Regards,
    Amin
 *  Thread Starter [buschwichtel](https://wordpress.org/support/users/buschwichtel/)
 * (@buschwichtel)
 * [6 months, 3 weeks ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18718407)
 * Hello, sorry for the delay.
 * I have now:
    - uninstalled the forminator plugin and reinstalled it
    - deactivated all other plugins and switched to one of the default themes (“
      twenty five”) to test the issue
 * This has resulted in some unexpected behavior. The site still crashes with an
   internal server error, only when forminator is activated (when it isn’t, it does
   load).
 * Meanwhile, the following error was logged twice, but no longer appears on subsequent
   attempts:
 *     ```wp-block-code
       [13-Nov-2025 16:08:42 UTC] PHP Notice:  ob_clean(): Failed to delete buffer. No buffer to delete in /homepages/30/d4297102870/htdocs/wordpress/wp-content/plugins/forminator/admin/abstracts/class-admin-module-edit-page.php on line 907
       ```
   
 * Instead, the website now does not log an error at all, in spite of it obviously
   crashing. The related settings in wp-config are as follows:
 *     ```wp-block-code
       define( 'WP_DEBUG', true );define( 'WP_DEBUG_LOG', true);define( 'WP_DISABLE_FATAL_ERROR_HANDLER', true ); define( 'WP_CACHE', false );
       ```
   
 *  Is there any alternative file that forminator might be logging into?
 * Best regards
 *  Plugin Support [Nithin – WPMU DEV Support](https://wordpress.org/support/users/wpmudevsupport11/)
 * (@wpmudevsupport11)
 * [6 months, 3 weeks ago](https://wordpress.org/support/topic/forminator-fatal-php-error/#post-18719462)
 * Hi [@buschwichtel](https://wordpress.org/support/users/buschwichtel/),
 * > Meanwhile, the following error was logged twice, but no longer appears on subsequent
   > attempts:
 * The above is more of a warning, in general, it shouldn’t have affected how the
   plugin would behave in the site.
 * Since the issue is still the same even after a conflict test possible to also
   share the Site Health Info? ie under your WP dashboard, Tools > Site Health >
   Info and by clicking the “Copy Site info into Clipboard” button.
 * You can share the file via Google Drive, Dropbox, Pastebin or any such cloud 
   services.
 * > Is there any alternative file that forminator might be logging into?
 * In general, fatal errors are logged via the debug.log files. However, can you
   try adding these to wp-config.php to debug, and check if you have any Forminator
   integration enabled to rule it out?
 *     ```wp-block-code
       define('FORMINATOR_DEBUG', true);define('FORMINATOR_ADDON_DEBUG', true);
       ```
   
 * ie
 * Update the debug as follows:
 *     ```wp-block-code
       define( 'WP_DEBUG', true );define( 'WP_DEBUG_DISPLAY', false );define( 'WP_DEBUG_LOG', true );@ini_set( 'display_errors', 0 );define( 'SCRIPT_DEBUG', true );define('FORMINATOR_DEBUG', true);define('FORMINATOR_ADDON_DEBUG', true);
       ```
   
 * And then check if there any further information picked in the debug.log files.
 * Looking forward to your response.
 * Regards,
 * Nithin

Viewing 7 replies - 1 through 7 (of 7 total)

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