realizing that the content of Mastodon DMs are accessible to you and your recipient(s)' administrators is a little scary, but!
(a) it's little different from how other social networks work and
(b) it might motivate you to explore what's called end-to-end encrypted messaging services, like Wire or Signal
Note: There are trade-offs to both of those options, and of course there are other services as well, but those two seem to be decent choices
I realize now that Wire link above isn't ideal for new users (thanks @lx4r for pointing the out)
Here's a nice guide to getting started with Wire: https://medium.com/@mshelton/wire-for-beginners-8ee6caef49cb (though it is on Medium fyi)
Also, note that both Wire and Signal are currently centralized services (unlike Mastodon!). As some have pointed out, there are federated/decentralized e2e options, including XMPP, @matrix and even PGP, but I (personally) find Wire & Signal easier to set up and use.
@schlink Absolutely! DMs are fine for “what’s for lunch”, but please don’t depend on their secrecy.
@schlink Not to forget about matrix.org and threema.ch
@schlink PGP and Keybase probably deserve a mention here as well.
@schlink Well, I mean, Twitter DMs are accessible to Twitter administrators, no?