It's been hilarious trying convey this to you guys. You designed it that way, it's not a user issue at all. If it helps sometimes it will say "Loading Proton Account..." for a couple seconds then "Loading Proton Mail..." for a couple more seconds.
I would say this is one reason not to use Proton - they treat you like this when you open a support ticket too, like it's impossible there's anything wrong and it's always user error. They're always confused as if nobody has ever reported it and you never arrive at a solution, you just get sick of talking with them after a while because they don't know their own product.