3.14.10: PHP Warning: Undefined array key “neutralize_shortcodes”

Hi Sarah,

I found the cause and a workaround for you.

The warning is from a new security function added in 3.14.10. When you use PHP 8.0+, it triggers an error in the merge tags system.

For now, here is a quick solution. Create a file named nf-fix-neutralize-shortcodes.php and upload it to /wp-content/mu-plugins/ folder. The warnings will stop right away.

<?php
/**
 * Plugin Name: Ninja Forms - Fix neutralize_shortcodes warning
 * Description: Fix PHP warning "Undefined array key neutralize_shortcodes" in Ninja Forms 3.14.10
 * Version: 1.0
 * Author: Faisal Ahammad
 */

add_filter('ninja_forms_merge_tags_other', function($tags) {
    if (!isset($tags['neutralize_shortcodes'])) {
        $tags['neutralize_shortcodes'] = array(
            'id'       => 'neutralize_shortcodes',
            'tag'      => '{neutralize_shortcodes}',
            'callback' => 'neutralize_shortcodes',
            'value'    => '',
        );
    }
    return $tags;
});

No activation needed from WordPress admin. Just put the file in the folder and it works.

Let me know if you need help.

Note for Ninja Forms developer team:

The __call method in includes/MergeTags/Other.php line 95 does not check if the key exists before accessing it:

return $this->merge_tags[$name]['value'];

In PHP 8.0+, call_user_func from global scope with protected method callback (like map_deep($value, [$this, 'neutralize_shortcodes'])) triggers __call instead of a fatal error. Since neutralize_shortcodes is not a merge tag key, it throws the warning.

Suggested fix: Add isset() guard:

public function __call($name, $arguments)
{
    if (isset($this->merge_tags[$name]['value'])) {
        return $this->merge_tags[$name]['value'];
    }
    return '';
}

Or change neutralize_shortcodes from protected to public. Same issue exists in Calcs.php:21 with calc_value.

Best regards,
Faisal (forum volunteer)