I dread Linux kernel updates. Still running a 4.4 era kernel. Kernel versions have always been hit or miss, some are good, others introduced a new bug. Sometimes it's necessary to upgrade glibc as well which is a huge pain.
People don't choose a Super LTS distro/kernel because they want newer kernel versions, they want stability. What the hell are you doing trying to shoehorn a newer kernel into Ubuntu 16.04?
Proton doesn't really host a standard email server like imap for you to access on the client side. You have to bridge/proxy/translate it. And Proton doesn't offer any of the convienences like distribution lists that you expect for the past 30+ years.
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