I use the coredev buildout for migration to py3. for the livesystem i use the official ploneinstaller 5.2. After copy filestorage/blobstorage to livesystem, if i check the plone-upgrade view in the zmi i get the following warning
Can i ignore this until the new release ist out ? or should i use the official ploneinstaller for migration?
In most cases you should be able to ignore this until the next release is out. It depends though on if you ran upgrade-steps that changes things that the current production-code does not support yet.
I see the step move_markdown_transform_settings_to_registry and the profile to_522 in https://github.com/plone/plone.app.upgrade/tree/master/plone/app/upgrade/v52. You should check if the changes made there conflict with your current site.
