marc2bibframe correctly places the paired 490/880 fields into a single Series Hub resource, but bibframe2marc creates a single 490 field with the two bf:mainTitle fields smashed together.
<marcxml:datafield tag="490" ind1="0" ind2=" ">
<marcxml:subfield code="a">Serii︠a︡ "Istorii︠a︡ ta polityka"Серія "Історія та політика"
</marcxml:subfield>
Using LCCN 2022470726 as the example.
marc2bibframe correctly places the paired 490/880 fields into a single Series Hub resource, but bibframe2marc creates a single 490 field with the two bf:mainTitle fields smashed together.
The output should be: