Prerequisites: An instance of an older version of XWiki (e.g. v 8.4.5) containing at least one sub-wiki and a newer version (to which will be migrated - e.g. v 9.6) are available.
STEPS TO REPRODUCE:
- Delete the "data" folder from the newer version
- Copy the "data" folder from the older version and paste it in the folder of the newer version
- Start XWiki
- Login as Admin
- Use the Distribution Wizard to complete the upgrade process
- Observe the install log
The upgrade to the newer XWiki version (e.g. v 9.6) is successfully completed without any errors.
When installing the standard flavor, some errors/warnings appear in the install log (screenshot attached), regardless of the configured database (HyperSQL, PostGreSQL, MySQL or Oracle).