[smtddr]

>>Also, even if it's non TLS/SSL, you're putting a lot of trust in Rainloop not being hacked or malicious.

I'm assuming that "non" shouldn't be there, so... I don't know how I feel about the whole curl/wget [url] | [interpreter] trend. In theory, it shouldn't really be that different from the days of downloading "setup.exe" and running it.

If for some reason you don't trust Rainloop then you shouldn't install anything of theirs no matter what the delivery method is.