This article is about ecumenical Masses; not about mixed marriages.
I want to know why you are defending ecumenical “masses”. Stay on topic.
"It's a sin for a Catholic to worship alongside heretics."
So I was asking for a clarification of your personal view, as applied to canonically permitted mixed marriages.
(2)You ask, "why [are] you are defending ecumenical masses?
I did not defend ecumenical masses.