ZipArchive

Error MT5211: Native linking failed, undefined Objective-C class: _OBJC_CLASS_$_ZipArchiveDelegate. If '_OBJC_CLASS_$_ZipArchiveDelegate' is a protocol from a third-party binding, please check that it has the [Protocol] attribute in its api definition file, otherwise verify that all the necessary frameworks have been referenced and native libraries are properly linked in. (MT5211)

After upgrading to Xamarin 4.2.4 , Mono 3.2.6 ZipArchive now throws these errors when building to Release

ZipArchive is used in 40 of our apps and has done amazing for the past year.