Problem with WPML 4.8 database tables optimization

Overview of the issue

WPML 4.8 includes a process to optimize the database tables which store details of translation jobs.

In a scenario where you have content translated with WPML pre-4.8 and also content translated after updating to WPML 4.8 and you then run the process, it can corrupt the storage of the WPML 4.8 translations.

This would be visible if you were using the Classic Translation Editor.

Workaround

WPML 4.8 includes a new built‑in troubleshooting feature to help automatically clean up and optimize these WPML tables. Please follow the instructions from this page: Optimizing WPML Database Tables.