Steps to replicate the issue

• Create a page with this Wikitext:

<ref name="a" /> <ref name="a" group="g" />
<references>
<ref name="a">Default group content</ref>
</references>
<references group="g">
<ref name="a">Custom group content</ref>
</references>

• Edit the page in VisualEditor

What happens?:

• The content reference that's defined in custom group is neither visible nor editable

What should have happened instead?:

• The content reference that's defined in custom group is should be visible and editable

Notes

It seems that VE relies on the group attribute being present for all refs. If it's not their there will be some confusion if the content was already stored in the InternalList.

See https://gerrit.wikimedia.org/g/mediawiki/extensions/Cite/+/0981f4a0deae9f1cc4177b2144a6bc611a99c317/modules/ve-cite/ve.dm.MWReferenceNode.js#102

I did dig for a MediaWiki version where this works. So far it's not working for versions till 1.39.8 from Oktober 2022