Ran into a localization issue like this after an upgrade and it turned out to be a cached translation record that didn't survive the clone properly. Worth checking your sys_translated_text and sys_ui_list tables for any missing French locale entries tied to those keyword-based navigation records. If dev works fine and prod doesn't after the clone, that's almost always a data discrepancy rather than a code problem — a Support case with both instance details will get you to the root cause faster than digging manually.
