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Problem:
On translated WooCommerce products, the _product_image_gallery meta stored in the database is correct per language. However, on the frontend, the gallery IDs returned by WordPress are different from what is stored in wp_postmeta.
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Specifically:
Direct SQL query via $wpdb returns the correct meta_value from wp_postmeta.
But get_post_meta(), get_metadata_raw(), and $product->get_gallery_image_ids() return a different set of IDs.
The returned IDs include values that are not present in the database for that product ID.
This results in the frontend gallery displaying images that do not match the stored _product_image_gallery for that translation.
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Environment:
WordPress + WooCommerce
WPML + WooCommerce Multilingual (WCML)
No Media Translation used
Each language uses its own attachments (separate media per language)
_product_image_gallery is correctly stored per translation in wp_postmeta
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Debugging steps performed:
Confirmed correct product IDs (example):
SK product ID: 8411
HU product ID: 8727
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Verified database content in phpMyAdmin:
wp_postmeta contains correct _product_image_gallery for both SK and HU products.
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Verified direct SQL via $wpdb inside template:
global $wpdb;
$post_id = $product->get_id();
$row = $wpdb->get_row(
$wpdb->prepare(
"SELECT meta_value FROM {$wpdb->postmeta} WHERE post_id = %d AND meta_key = %s",
$post_id,
'_product_image_gallery'
)
);
var_dump( $row );
This returns the correct meta_value from the database.
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Verified get_metadata_raw():
get_metadata_raw( 'post', $product->get_id(), '_product_image_gallery', true );
This returns a different value than the direct SQL query.
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Inspected filters on get_post_metadata via WP-CLI:
wp eval '
global $wp_filter;
$hook = "get_post_metadata";
foreach ( $wp_filter[ $hook ] as $priority => $callbacks ) {
foreach ( $callbacks as $cb ) {
$fn = $cb[ "function" ];
if ( is_array( $fn ) ) {
$name = ( is_object( $fn[ 0 ] ) ? get_class( $fn[ 0 ] ) : $fn[ 0 ] ) . "::" . $fn[ 1 ];
} else {
$name = $fn;
}
echo $priority . " => " . $name . "n";
}
}
'
This revealed:
WCML_Product_Gallery_Filter::localize_image_ids
hooked into get_post_metadata at priority 10.
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Root cause:
WCML_Product_Gallery_Filter::localize_image_ids filters get_post_metadata and overrides the _product_image_gallery meta at runtime, even though the database contains correct per-translation values.
Expected behavior:
If each translation has its own _product_image_gallery stored in wp_postmeta, WCML should not override those values during metadata retrieval.
Actual behavior:
WCML modifies _product_image_gallery during get_post_metadata, causing frontend gallery to use a different set of attachment IDs than what is stored in the database.
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Temporary workaround:
Removing the WCML filter restores correct behavior:
add_action( 'init', function () {
global $wp_filter;
if ( isset( $wp_filter[ 'get_post_metadata' ] ) ) {
foreach ( $wp_filter[ 'get_post_metadata' ]->callbacks[ 10 ] as $callback ) {
if (
is_array( $callback[ 'function' ] ) &&
is_object( $callback[ 'function' ][ 0 ] ) &&
get_class( $callback[ 'function' ][ 0 ] ) === 'WCML_Product_Gallery_Filter'
) {
remove_filter(
'get_post_metadata',
$callback[ 'function' ],
10
);
}
}
}
} );
After removing this filter, the frontend correctly uses the raw _product_image_gallery stored in the database.
Questions:
Is WCML intended to override _product_image_gallery even when translations have their own gallery meta stored?
Is there an official way to disable WCML gallery localization without manually removing the filter?
Should WCML respect per-translation _product_image_gallery values stored in wp_postmeta?
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