TYPO3 Core

In case a TCA field uses allowLanguageSynchronization (or l10n_mode=exclude) for table pages_language_overlay, dependencies (localizations of the initial record) are processed that point to the according pages_language_overlay. However pages_language_overlay records cannot be localized further, they always depend on a single pages record which is the record of the default language.

In case the backend is used as non-admin user that has a language restriction ("Limit to languages" in backend groups/users settings), an error message is shown:
[newlog()] recordEditAccessInternals() check failed. [ERROR: Language was not allowed.]

In TYPO3 v8, all pages_language_overlay records are selected which match the condition pages_language_overlay.pid = pages_language_overlay.uid (pid is used as transOrigPointerField). In TYPO3 v9 this changed since pages_language_overlay has been migrated into pages having a distinct transOrigPointerField in l10n_parent.