Plugin Issue

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

Problem:
The client reported an issue where the 'Add Module' button and content manipulation functionalities were non-responsive in the 'Case Studies' post type using the Classic Editor. This was due to a JavaScript error caused by the ACFML plugin attempting to execute a function meant for the Block Editor, resulting in a 'wp is not defined' error and breaking the page's JavaScript.
Solution:
We recommended the following steps:
1. Temporarily deactivate the ACFML plugin to check if the issue resolves.
2. Enable WP_DEBUG in the wp-config.php file to gather more detailed error logs. The specific lines to add were:

define('WP_DEBUG', true);<br />ini_set('log_errors', TRUE);<br />ini_set('error_reporting', E_ALL);<br />ini_set('error_log', dirname(__FILE__) . '/error_log.txt');

3. If the issue persists, switch to a default WordPress theme like Twenty Twenty Five to determine if the issue is theme-specific.
4. If the problem is resolved by switching themes, it suggests that the issue might be with the custom theme used on the site rather than the WPML or ACF plugins.

If these steps do not resolve the issue or if the solution seems outdated or irrelevant to your case, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix,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 further assistance is needed, please open a new support ticket at WPML support forum.

This is the technical support forum for WPML - the multilingual WordPress plugin.

Everyone can read, but only WPML clients can post here. WPML team is replying on the forum 6 days per week, 22 hours per day.

Tagged: Custom Work

This topic contains 25 replies, has 2 voices.

Last updated by steveR-27 2 months ago.

Assisted by: Bobby.

Author	Posts
April 29, 2026 at 7:27 am #18001611
steveR-27	Hi Guys, Is there any response on this? My client is very eager to getting this working! Thanks, Keelan
April 29, 2026 at 7:30 am #18001613
steveR-27	Hi Bobby, Apologies, when I sent my last message, your last message from 7:00 wasn't showing for me. Thankyou for this clarity. I understand that bugs can be fixed when plugins get updated - but please can you investigate further ASAP, and let me know if an update is the only thing that fixes the issue, or if there's something in the core plugin code itself that's causing this issue and what the resolution is for us? Thanks, Keelan
April 29, 2026 at 9:16 pm #18004102
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	Hi Keelan, Just to confirm, I have escalated this to our second tier team, and I will update you as soon as I have feedback.
April 29, 2026 at 10:53 pm #18004129
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	Additionally it looks like your theme is most likely pushing the use of Classic Editor. If you go to CPT UI -> Edit Post Types -> Show in REST API and set to "yes" then the editor uses Guttenberg. When I attempted to try this with your Theme activated it crashed the page, but deactivated it worked. I will update more as soon as I have feedback from our team.
April 30, 2026 at 10:37 am #18005295
steveR-27	Hi Bobby, We're not using Guttenberd, which intentionally using the Classic Editor as that's what works for us. Please can this be escalated more quickly as I feel like the issue has been clearly stated and just needs a fix, recommended by ACF. Please keep me posted. Thanks, Keelan
April 30, 2026 at 5:24 pm #18006633
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	This has been escalated to our second tier and we will get back to you as soon as there is feedback. Thank you!
May 7, 2026 at 4:06 pm #18021075
steveR-27	Hi Bobby, Any update on this at all? Thanks, Keelan
May 7, 2026 at 6:50 pm #18021290
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	Hi Keelan, We are still reviewing this, however, so far the feedback is that this is pointing to the custom theme. The theme also has some custom code with a hard-coded dependency on the ICL_LANGUAGE_CODE, which can cause Fatal errors when WPML is deactivated. to help with that we edited the file in question (which is for a language switcher), namely themes/mintcake-flexible/template-parts/language-select.php, and added this to the top: if ( !defined( 'ICL_LANGUAGE_CODE' ) ){ return; } So the WPML-related error disappears. I would highly recommend contacting the custom theme developers about this issue. Did you create the theme yourself, somebody in your team or via an external agency?
May 8, 2026 at 10:55 am #18022535
steveR-27	Hi Bobby, So I've just switched the theme back to our Mintcake one, gone to the backend of a case studies post, added your code at the top of the php file (just after the opening php tag), refreshed the backend, and I still see the same 2 console errors: hidden link post.php?post=8489&action=edit&lang=en:189 Uncaught TypeError: Cannot read properties of undefined (reading 'dispatch') at post.php?post=8489&action=edit&lang=en:189:13 at post.php?post=8489&action=edit&lang=en:203:6 post.php?post=8489&action=edit&lang=en:932 GET hidden link 404 (Not Found) I don't see any difference. It does appear to be theme related, but it's not clear why at all. ACF managed to create a new post type, create a post, and not see the issue at all, which they're suggesting is transient data interrupting something. Is ACF's previous statement "The ACFML plugin is throwing a fatal_ wp is not defined _error on a classic editor post type because it is blindly attempting to execute_ wp.data.dispatch('core/notices')_. This crashes the page's JS and breaks third-party interface buttons." not valid in this situation? It seems like a very reasonable explanation as to why the issue is happening, we're using a classic editor which your plugin wasn't expecting and it's breaking the JS on the page. Thanks, Keelan
May 11, 2026 at 10:51 pm #18028775
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	Hi Keelan, I have passed this info to our team, however, our plugin does not have any known issues with the Classic Translation Editor. At the moment it looks like a code within the custom theme is not working well. It is important to note that custom code support is usually limited. Are you familiar with your theme's code or would the developer happen to work in your team? It would greatly help to get feedback as well from the theme developer.
May 12, 2026 at 1:24 pm #18030667
Nigel WPML Supporter since 02/2016 Timezone: Europe/Madrid (GMT+02:00)	Hi Keelan My name is Nigel and I am a second tier supporter, and I wanted to communicate with you directly to be clear about the status of this issue, as I understand you are expecting an update. Although this problem relates to a custom theme and that limits the extent to which we are normally able to help, that is not what is stopping me from resolving your problem, and I do want to help. The difficulty is that the ACF repeater fields UI does not work with Case Study posts even when all WPML plugins are disabled. Normally I would investigate a problem where something works, but stops working when WPML is involved. In this case we have something that doesn't work, and it continues to not work when WPML is involved. Yes, a JS error appears in the console, but that is not what is preventing the ACF repeater fields working. I will see if I can reproduce the JS error appearing in the console, but it is cosmetic and does not affect the ACF repeater fields. Crucially, if I fix that JS error it will not fix the actual problem you are reporting, which is caused by your theme. If you check your staging site I have disabled all plugins except for ACF Pro and CPT UI. While your custom theme is active, when editing a Case Study post the ACF repeater fields do not work. Switch theme and then they do work. And if you then activate the WPML plugins you will see that they continue to work. I suggest your theme developer work on resolving the problem with just ACF Pro and CPT UI active; when it works in that context I expect that it will work when other plugins such as WPML are added to the mix, and if it does not I will look again to identify why. We'll wait to hear from you to see if further help is needed.
May 19, 2026 at 8:52 am #18044958
steveR-27	Thankyou to the WPML team for going above and beyond with this - we got to the bottom of the issue ourselves which was relating to an ACF function that had been manually added by a developer who is no longer with the company. This was a function written in the functions.php file which was 'renaming' ACF Fields in the backend and erroring, causing the page to break. We only discovered this when we drilled right in to the Console Error on the page, which told us exactly which file and line the issue was coming from. Thank you for persisting to help with us. Thanks, Keelan