This thread is resolved. Here is a description of the problem and solution.
Problem:
The client was unable to preview or update posts in both the original French and the English translation after creating a translation using WPML. They encountered a 403 error, which persisted even after deactivating all plugins except for essential ones. The issue was linked to the 'aioseo' plugin triggering Apache's mod_security 'critical' alerts, which blocked the capability to save a post.
Solution:
We recommended deactivating all plugins except for the WPML ones to check if the issue persists. The client discovered that the 'aioseo' plugin was the cause of the 403 errors. Disabling or adjusting the settings of the 'aioseo' plugin should resolve the issue.
If this solution does not apply to your case, or if it seems outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have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 our support forum.
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