The code has been ported to the operator+rna system, however, there are currently issues related to how the pointer-rna's work for use as operator properties. (NOTE: RNA_property_pointer_set only takes into account builtin props for now, but not id-props, while the corresponding get method seems to take them into account)
The alternative to using pointer-properties for the operator, is to store strings and look up the relevant objects later, but there should be a nicer way...
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