@soudk Its actually really easy. If you don't want the fastest, I'd recommend using the Snap package. TLG has a decent tutorial regarding the Snap version if I recall correctly.
Here's a list of reasons why I think ProtonMail is shady and will never trust them:
The developers of ProtonMail, don't even use ProtonMail, they use almost exclusively GMail or Outlook.
They don't let you register over their .onion. If you go to their .onion and then click register, it redirects you to their
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