Update. More on the EC plan for Open Research Europe (#ORE) to adopt an #OpenSource core.
https://op.europa.eu/en/publication-detail/-/publication/3603e219-6a65-11ef-a8ba-01aa75ed71a1/language-en

See §2.4.5. "ORE will be underpinned by an #OpenSource software #infrastructure, the core elements of which will be developed with the support of the Commission and will follow #OpenStandards. Its infrastructure will be in line with the Principles for Open Scholarly Infrastructure [#POSI] and with the Open Source Software Strategy of the European Commission."

Open research Europe - Publications Office of the EU

This report puts forward a vision for Open Research Europe as a collective non-profit open access publishing service for the public good.

^{Publications Office of the EU}