All of the recent ePub 3 eBooks I've seen don't actually need to be ePub 3. There's nothing in them that cannot be done 100% as ePub 2. I don't know why publishers have to move to ePub 3 (when they don't need any ePub 3 features) when it would be better for comparability with older software to stay ePub 2.
If Kobo is automatically making a kepub when the system sees the eBook is ePub 3, then we are going to see a lot of lost sales there because of the increase of ePub 3 being made.
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