Forminator Fatal PHP error

  • Resolved buschwichtel

    (@buschwichtel)


    7 months, 1 week ago

    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

    [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:99
    Stack 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

    (@wpmudev-support7)

    7 months, 1 week ago

    Hello @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

    (@buschwichtel)

    7 months, 1 week ago

    Hello @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

    (@wpmudevsupport14)

    7 months, 1 week ago

    Hi @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

    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

    (@wpmudev-support7)

    7 months, 1 week ago

    Hello @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

    (@wpmudev-support2)

    6 months, 3 weeks ago

    Hello @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

    (@buschwichtel)

    6 months, 3 weeks ago

    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:


    [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:

    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

    (@wpmudevsupport11)

    6 months, 3 weeks ago

    Hi @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?

    define('FORMINATOR_DEBUG', true);
    define('FORMINATOR_ADDON_DEBUG', true);

    ie

    Update the debug as follows:

    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)

The topic ‘Forminator Fatal PHP error’ is closed to new replies.