Fatal Error: InvalidArgumentException in Obj.php:112 with PHP 8.2

This thread is resolved. Here is a description of the problem and solution.

Problem:
You are experiencing a fatal error on your site due to a compatibility issue between PHP 8.2 and how WPML handles Gravity Forms' required indicators.
Solution:
We recommend deactivating the Nelio AB Testing plugin to see if the issue persists. If deactivating the plugin resolves the issue, it indicates that the Nelio AB Testing plugin might be contributing to the conflict. If the error continues, it suggests that the problem is specifically related to WPML and Gravity Forms under PHP 8.2.

Please note that this solution might be outdated or not applicable to your specific case. We highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the problem persists, please open a new support ticket at WPML support forum for further assistance.

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Tagged: Exception

This topic contains 2 replies, has 1 voice.

Last updated by Andrey 1 week ago.

Assisted by: Andrey.

Author	Posts
April 13, 2026 at 7:42 pm #17966959
fleetupf	Hello, I am getting a fatal error on my site. - WordPress: 6.9.4 - PHP: 8.2.30 - Plugin: WPML Multilingual CMS (4.9.2) & Gravity Forms Error details: Uncaught InvalidArgumentException: item should be a Collection or an array or an object in .../vendor/wpml/fp/core/Obj.php:112 This seems to be a compatibility issue with PHP 8.2 and how WPML handles Gravity Forms' required indicators. My host (WP Engine) confirmed this is a code-level issue. Could you please provide a fix or a patch?
April 14, 2026 at 5:38 pm #17969739
fleetupf	I contacted WP Engine support as you suggested. However, they informed me that because my site is on a "Shared Environment," they are unable to manually flush the PHP OPcache or restart the PHP-FPM process for an individual site. Since I cannot perform a server-side PHP reset, are there any other steps I can take? For example, is there a specific setting in WPML I should change, or a patch available for this InvalidArgumentException under PHP 8.2? Also, I found that disabling the 'Gravity Forms Partial Entries' and 'Nelio AB Testing' plugins seems to have temporarily stopped the errors. Does this give you any more insight?
April 15, 2026 at 8:01 am #17970487
Andrey WPML Supporter since 06/2013 Languages: English (English ) Russian (Русский ) Timezone: Europe/Kyiv (GMT+03:00)	Thank you for contacting WPML support. What are the results if you just deactivate the Nelio AB Testing plugin? Do you still experience the issue?