I'd add to that, a possible single point of failure for us as users: CEO Bron Gondwana. Bron also shares out his own time for a technical standards effort -- "J

I'd add to that, a possible single point of failure for us as users: CEO Bron Gondwana. Bron also shares out his own time for a technical standards effort -- "JMAP". OTOH, if you're in the US, the next step up in perceived national security threat might well see Protonmail getting blocked. Fastmail, with five eyes on it, maybe not so likely to just "disappear".