Thanks for spelling it out. You really shouldn't ever lose your chat history, but it sounds like something is going horribly wrong on your encryption. As part

Thanks for spelling it out. You really shouldn't ever lose your chat history, but it sounds like something is going horribly wrong on your encryption. As part of the funding we're setting up a dedicated crypto team (at last) to focus on nothing but the remaining encryption problems. It's super embarassing that these failure modes can still exist today though - sorry :(