Francis fought the Roman Mass already as Buenos Aires Archbishop after Benedict XVI published his 2007 Motu Proprio Summorum Pontificum.
He allowed a Roman Mass in the Sacred Heart chapel in Flores, central Buenos Aires. The Archdiocese has - theoretically - 3 Million Catholics. A group including many young people attended this Mass for about three years until Bergoglio suspended it in June 2010.
This and other refusals to allow the Roman Mass were documented by Pagina-Catolica.Blogspot.com.
Priests willing to celebrate the Roman Mass ran against Bergoglio's secret provision that the Roman Liturgy could only be celebrated in two places: Our Lady of Mount Carmel and St Michael the Archangel where the Novus Ordo readings were imposed on the Roman Rite and read by laypersons, both men and women. But even in these two chapels this abusive form of the Roman Mass was eventually cancelled..