Users with custom user role not appearing in author dropdown

I’ve created a custom user role ‘staff’ on my WordPress site, however users with this role do not appear in the author dropdown when I edit posts either with the standard editor or quick edit.

I believe this to be because an old bug in the WordPress core – #16841 – which recommends adding the depreciated capability of ‘level_1’ to your user role to fix the issue.

However having done this my users with the custom user role still do not appear in the dropdown. Are you aware of this issue? If so could you please recommend a workaround?

Thanks.

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