Performance

Problem:
The client reported slow load times when the WPML String Translations plugin is enabled. They noticed that disabling the plugin significantly speeds up the page loads. They also mentioned using the Index WP MySQL For Speed plugin, which only slightly improved the situation. The client was concerned about the storage of translation files and the potential impact of custom actions on performance.
Solution:
We recommended the following steps to troubleshoot and potentially resolve the issue:
1. Use the Query Monitor plugin to compare performance with and without WPML plugins enabled to help identify slow queries.
2. Ensure all WPML plugins are updated to the latest versions.
3. Test in a minimal setup by switching to a default theme, such as Twenty Twenty-Four, and disabling all plugins except WPML and ACF. Then, gradually re-enable the theme and other plugins to check if a specific component is causing the issue.
4. If the issue persists with only WPML and the default setup, it might be a WPML-specific issue, which we will investigate further.
5. Check with the hosting provider to review server load, cache, or configuration differences, as the local environment was much faster than production.
6. If applicable, provide a staging site or a duplicator package for further investigation.
7. Since the issue related to a read-only languages directory mentioned in the Pantheon errata does not apply (as translations are being generated and stored), there is no need to apply the workaround in wp-config.php.
8. Removing the

after_setup_theme

action could help improve performance if it was doing additional processing on every request.

If these steps do not resolve the issue or if the solution seems outdated or irrelevant to your case, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix,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