Content Translation Module Error

Does this site use memcache? If so, it could be #3164651: Errors for content translation module →

I agree that we need to know how to reproduce this before we can work on resolving it.

While this was reported on 10.1, any fix will be applied to 11.x (main) first.

I occasionally encounter this error on multilingual websites as well. It typically resolves with a cache clear via `drush cr` or by running `drush ev "drupal_flush_all_caches();"`.