From 3.1 to 3.2

User write access

To fix an issue where user owned access collections like Friends or Friend Collections would still show in the access drop down when creating content, even if related plugins are disabled, we needed to change some internal logic. If you want to have an access collection subtype available in the write access you now need to register the subtype with a plugin hook. See the plugin hook reference for “access:collections:write:subtypes” for more details.

River items enabled state

The enabled state of river items has been deprecated. You should no longer use this property when working with river items.