As for Catholics in Protestant churches, communion there is open to all including small children who see it as snacks(inappropriate in my view)
It is up to the Catholic if he can believe in the same eucharistic transformation in that environment of different believers, without a priest, and coming from a server who doesn't believe as he does. If I was Catholic I would not
meh, what do I know, just a churchless methodist who goes to mass and hasn't taken commnunion in 3 years
Catholicism does not permit a Catholic to receive communion in a Protestant Church, whether or not the Protestant Church allows it.
I don't presume to know what your other beliefs or convictions might be, but I do appreciate your thoughtfulness on this one. You have a hold on the truth. I will pray that that "hold" will bring you along, at last, to the fullness of the Feast.
If I may point out something here, not all Protestant Churches see Communion as open or allow small children to participate. The Church where I grew up, which is a FreeWill Baptist Church, saw it as closed only to Christians due to the restrictions placed on the service in 1 Cor. 11 and would not allow children to participate because of this passage. The warning in verses 27-29 was proclaimed so that each person taking part in the service knew exactly what was at stake before taking part and we combined the service with a footwashing service immediately after Communion.
It was drilled into me from a young age that this was not a trivial matter and that it was among the most Holy and reverent of services that we had, second only in importance to an alter call or believer's baptism.
I don’t know what churches you’ve been to but I’ve attended Presbyterian, Baptist, Assemblies of God, Lutheran, non-denominational, and not one of those churches practiced totally open communion. Some didn’t fence the table as well as I expect my Presbyterian ministers to do, but none allowed “small children” to “see it as snacks”. Not even the groups that view communion as a mere memorial rather than some more spiritual reality.
And most properly-educated Protestants would not attempt to receive in a Catholic mass either. I don’t, because I know they don’t want me to and I also know that I disagree with them about what specifically the sacrament means. So I don’t kneel and I don’t go forward and it’s not that big a deal.