This is by design and now it just works. All sats is public, but the DM message content is encrypted.
Discussion
This is still a liability, like if you message nostr:npub1dergggklka99wwrs92yz8wdjs952h2ux2ha2ed598ngwu9w7a6fsh9xzpc or anyone and then it turns out someone cracks their nsec or something, they have the entire conversation history, unless of course "all" the relays no longer have those messages saved.
