Hi @felixhelix,
Unfortunately this is a known issue when upgrading from 3.1.2, where the fieldname becomes “licenseUrl” instead of “licenseURL”. Manually changing this in the Database brings the Information back in the article view.
A fix for this was applied to OJS 3.2, but upgrading directly to 3.3 unfortunately still produces the discrepancy in the database. You can either upgrade to OJS 3.2 first, or run that query to fix it after upgrading directly to OJS 3.3.