Just in case your real name is Rip van Winkle, I’ll let you in on a little secret. The Catholic Mass has been here since the start of the Church, and it is still here, in numerous rites, including the Roman or Latin rite, which is celebrated around the world according to the rite promulgated by Pope Paul VI. She hasn’t lost her Catholic Mass; it has been here all along. The rite is slightly different - and in truth, the differences are truly slight - between the rite as promulgated by Pope Paul VI and the rite prior to that in the Roman, or Latin rite. In fact, the Catholic Mass is still here in other rites, of which you appear to be non cognizant of, such as the Maronite rite, and the Byzantine rite, just to name two. In fact, the differences between those valid rites and either the Roman or Latin rite Mass, either before or after Pope Paul VI’s changes, are more different from the pre-Paul VI and post-Paul VI rites than they are from each other.