Comment 5 for bug 101456

Yes, Products.Silva.upgrade_220 has a MetadataUpgrader, which migrates metadata from obj._portal_annotations to a real Zope3 annotions object, then copies over the metadata from the old to the new. Ouch, expensive for sure in large installations. IN the old metadata way, _portal_annotations is a dictionary with the namespace URI as the key, and the metadata for that set as the value. So, during the upgrader instead of copying directly, change the namespace if needed and then copy. I can't image this would add much additional time to this already expensive upgrade.

Your call.

notal appears to be used only once in the silva core, in views/edit/Container/docma_queue.pt. I think it was intended for 'disabling' a tal statement. This would be easy to standardize, as it's only in page templates.