Fix migration from schema <= 12 to schema > 16. Issue #1282

[N-Pex]

Signed-off-by: N-Pex npexdev@gmail.com

Pull Request Checklist

• Pull request is based on the develop branch
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[pixlwave]

Thanks for the PR @N-Pex and sorry for the long delay in reviewing. This looks good to me, although there is one small tweak we could make:

• It would make more sense to wrap the entire enumerateObjects call in the new if block, as there is no need to run this step if it's not going to perform any actions.