I can't imagine anyone would loose their testimony over this issue and I do hope that people will not judge each other no matter what personal decision they make for themselves.
So far, our Stake President is giving everyone a choice regarding the masks. We are to be respectful and social distance.
His emphasis is that we absolutely do not judge others or have any contention or problems because of choices we each have to make. I'm a big advocate of having the right to choose and don't want to see anything forced on anyone here. So far, I've seen members handling this very well too