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[Resolved] Found an error on the logs that we need to know why its happening
This thread is resolved. Here is a description of the problem and solution.
Problem: You are encountering an error in your logs indicating that the cache keys 'product_cat' and 'product_tag' are incompatible with prefetching, and the group 'WPML_Slug_Translation_Records::taxonomy' should be added to the list of non-prefetchable groups. You are concerned about the importance of this error and how to resolve it. Solution: We have consulted with our second-tier team and discovered that the WPML plugin defines cache groups for various text domains, which might be causing the notices from Object Cache Pro. The current constant used might not support wildcards, unlike the 'WP_REDIS_CONFIG' which does. We recommend defining this in your wp-config.php file:
This configuration should address all variations of the cache group names. However, these warnings might be informational and may not require action if your system operates normally. We suggest verifying this with Object Cache Pro support. If this solution does not resolve your issue or seems irrelevant due to updates or differences in your setup, please check related known issues at https://wpml.org/known-issues/, verify the version of the permanent fix, and ensure you have the latest versions of themes and plugins installed. If further assistance is needed, we highly recommend opening a new support ticket with us.
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Background of the issue:
I found an error on the logs and need to understand why it's happening. We found this error on the error log: 2025/07/04 14:54:15 [error] 11480#11480: *479993 FastCGI sent in stderr: "PHP message: objectcache.notice: The cache key `product_cat` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link; PHP message: objectcache.notice: The cache key `product_tag` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link" while reading response header from upstream, client: 66.249.68.39, server: woocommerce-245274-4383778.cloudwaysapps.com, request: "GET /wp-content/uploads/breeze/facebook/fbevents.js HTTP/1.1", upstream: "hidden link:", host: "www.pro-carbonracing.com", referrer: "hidden link". We need to know how important this is and how to fix it. I don't know if this is affecting other parts of the website.
Symptoms:
The error log shows that the cache key `product_cat` and `product_tag` are incompatible with prefetching, and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups.
Questions:
How important is this error?
How can I fix this issue?
Languages: English (English )German (Deutsch )French (Français )
Timezone: Europe/Zagreb (GMT+02:00)
Hi,
This doesn’t usually break the site, but it may affect performance or cache consistency for things like translated slugs, especially in WooCommerce taxonomies (`product_cat`, `product_tag`).
To help clarify the situation:
1. Have you added or customized any cache groups in your object cache configuration?
2. Are you using Redis or Memcached with Object Cache Pro?
3. Did you recently make changes to how caching is handled for taxonomies or WPML-related data?
If this cache group is not excluded from prefetching, you can resolve the warning by adding it to the `non-prefetchable-groups` list as described here: hidden link
Let me know what your current caching setup looks like, and I can help guide you further.
We're encountering website timeouts and plugin disabling when adding product category translations. This issue appears to be directly tied to the translation process.
Our current configuration uses Redis with Object Cache Pro and WP Rocket (preload active, no exclusions). We haven't recently adjusted cache settings or groups.
Could you advise on adding an exclusion to address this, if you believe it's the cause?
Does it help? Also, when you encounter timeouts during the translation, can you share server and WordPress debug logs that show at that time?
To further confirm whether caching is the root cause, you could try temporarily disabling Object Cache Pro (or Redis object caching) while performing a product category translation. If the process completes without timeouts or errors, that strongly points to cache interference.
I think the error is still showing
[08-Jul-2025 15:39:14 UTC] objectcache.notice: The cache key `product_cat` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link
[08-Jul-2025 15:39:14 UTC] objectcache.notice: The cache key `product_tag` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link
I will sent you the logs as soon as the error presents itself. I requested my client to try again and he will let me know the times for it
The error is presisting and here are the details
[11-Jul-2025 10:31:29 UTC] objectcache.notice: The cache key `product_cat` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link
[11-Jul-2025 10:31:29 UTC] objectcache.notice: The cache key `product_tag` is incompatible with prefetching and the group `WPML_Slug_Translation_Records::taxonomy` should be added to the list of non-prefetchable groups. For more information see: hidden link
other ones
[11-Jul-2025 10:31:52 UTC] PHP Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the
woocommerce-aelia-currencyswitcher
domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the
init
action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /home/245274.cloudwaysapps.com/qjezzcvrjc/public_html/wp-includes/functions.php on line 6121
[11-Jul-2025 10:31:52 UTC] PHP Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the
woocommerce-wholesale-prices-premium
domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the
init
action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /home/245274.cloudwaysapps.com/qjezzcvrjc/public_html/wp-includes/functions.php on line 6121
[11-Jul-2025 10:31:52 UTC] PHP Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the
wp-asset-clean-up
domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the
init
action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /home/245274.cloudwaysapps.com/qjezzcvrjc/public_html/wp-includes/functions.php on line 6121
[11-Jul-2025 10:31:53 UTC] PHP Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the
acf
domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the
init
action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in /home/245274.cloudwaysapps.com/qjezzcvrjc/public_html/wp-includes/functions.php on line 6121
Languages: English (English )German (Deutsch )French (Français )
Timezone: Europe/Zagreb (GMT+02:00)
Could you please provide me with the following:
- WordPress admin credentials (temporary access is fine, if preferred).
- A brief description of how and where this error occurs—for example, what actions you're taking or which page is being accessed when the message appears.
Languages: English (English )German (Deutsch )French (Français )
Timezone: Europe/Zagreb (GMT+02:00)
Since Object Cache Pro is a commercial plugin, the next logical step would be to reach out to their support team and ask the following:
Why are these notices still appearing even though WPML_Slug_Translation_Records::taxonomy has been explicitly excluded from prefetching?
Does it actually matter—is this just harmless logging, or could it lead to real issues?
At this point, we're not seeing a clear cause or way to reproduce the issue, given that you already applied the recommended configuration (excluding `WPML_Slug_Translation_Records::taxonomy` from `non_prefetchable_groups`), which should have stopped these notices.
It’s possible this is expected behavior or just a quirk in how the plugin handles certain cache groups, but their support team would be best positioned to confirm that and advise on any next steps.
Would you be able to bring this to their support? We're happy to assist further once we have more clarity from their end.
After a close inspection of the errors, I noticed that the error we excluded, 'WPML_Slug_Translation_Records::taxonomy', worked but the new one that was showing was 'WPML_Slug_Translation_Records::post', so I added that in teh rule to.
I do have a new one showing and here is what it refers to
[29-Jul-2025 08:48:09 UTC] objectcache.notice: The cache key `admin_texts_wpseo_social` is incompatible with prefetching and the group `WPML_Register_String_Filter` should be added to the list of non-prefetchable groups. For more information see: hidden link
The group is WPML_Register_String_Filter and I have added that as well but it didnt remove it
define('OBJECT_CACHE_PRO_NON_PREFETCHABLE_GROUPS', [
'WPML_Slug_Translation_Records::taxonomy',
'WPML_Slug_Translation_Records::post',
'WPML_Register_String_Filter',
]);
Languages: English (English )German (Deutsch )French (Français )
Timezone: Europe/Zagreb (GMT+02:00)
I've checked this with our 2nd tier team.
Here’s what we found:
* The WPML plugin defines cache groups not only for `'WPML_Register_String_Filter'` but also for variants like `'WPML_Register_String_Filter::domain'`, depending on the text domain being registered.
* These variant group names could be what’s triggering the Object Cache Pro notices.
* The constant you're currently using (`OBJECT_CACHE_PRO_NON_PREFETCHABLE_GROUPS`) might not support wildcards. However, the documentation linked in the warning refers to a different constant: `WP_REDIS_CONFIG`, which does support wildcards.
This approach should cover all variations of the cache group names.
It is possible, though that in many cases, these warnings are just informational and don’t require further action if the system runs as expected. You could double check this with Object Cache Pro support as we can't confirm this.
Let us know how it goes, and we’re happy to follow up if needed.
