The core script ``l10n_fr_account/migrations/2.1/end-migrate_update_taxes.py``
calls ``account.chart.template.try_loading('fr', company)``. During
``_post_load_data``, Odoo 18 resolves the French template's default accounts via
``self.ref()`` WITHOUT ``raise_if_not_found=False`` (chart_template.py:711/714
and the ``_get_property_accounts`` loop at :746). If any expected
``account.<company>_<key>`` xml-id is missing, it raises
``ValueError: External ID not found`` and aborts the registry load.
This happens when a database customized its chart of accounts: the generic PCG
account was deleted (e.g. 607000) or recreated without its xml-id (e.g. 707000).
Add a generic ORM ``post-migration`` script that, for every company with a
``chart_template``, reads the expected account xml-ids from the template API
(``_get_property_accounts`` / ``_get_chart_template_data`` /
``_get_account_account``) and recreates any missing ``account.<company>_<key>``
``ir.model.data`` pointing to the best matching account: exact code, else the
company account sharing the longest common code prefix, else a non-blocking
warning. It runs at stage ``post`` (before the native ``end`` script) and only
creates missing xml-ids — no account is modified. Idempotent, generic across
all migrated FR databases.
Remove the previous hardcoded 607/707 SQL block from
``versions/18.0/pre_upgrade.sh`` now superseded by this script.
bc3907e1d8