I suspect the proton thingy is the email thread. Even gmail sends qsc replies into spam folder when the thread gets too long.I just sent a proton email to them asking for a price list. I received the updated price list 2 minutes later.
I have never had a email bounce back from qsc or any source. But as a backup, I did set up a tuta email. Heads up, Tuta took 2 days to approve my new free email account to let me send/receive emails. So, if your in a rush to send a email, your better off to set it up now.
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