[Cryptography] any reviews of flowcrypt PGP for gmail?

[John Denker]

Has anybody vetted flowcrypt?  It purports to provide PGP for gmail.

  https://chrome.google.com/webstore/detail/flowcrypt-encrypt-gmail-w/bnjglocicdkmhmoohhfkfkbbkejdhdgc

It claims to provide "end to end" crypto, but as we've seen lately,
that doesn't always mean what we might want it to mean.

It also claims to be easy to set up and use.

I know nothing about it; I only learned of it recently.