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Problem:
If you're experiencing issues with product variants disappearing after updating WooCommerce Multilingual & Multicurrency to version 5.3.9, it might be due to conflicts with other plugins or themes.
Solution:
We recommend the following steps to troubleshoot and resolve the issue:
1. Ensure that only WooCommerce, WPML, and our addons are enabled when updating to the latest version of WooCommerce Multilingual & Multicurrency.
2. If the issue persists, try enabling all plugins and the child theme again to check if the problem still does not occur.
3. On your live site, delete any minified files created by Assets Cleaner PRO and clear the site's cache before updating.
4. Check for configuration issues under WooCommerce > WooCommerce Multilingual & Multi-Currency > Status.
5. Go to WPML > Settings > Post Type Translation and set "Variations (product_variation)" to "Translatable - only show translated items" and save the settings.
6. In WPML > Settings > Custom Fields Translation, click "Show system fields" and set the field

to "Translate".
If these steps do not resolve the issue, the solution might be outdated or not applicable to your specific case.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.