I believe it is using SimpleLogin in the background. I tested out simple login integration with bitwarden and found the proton pass implementation, plus integration with proton mail to be far superior. I use a fake email with every new sign up and don’t really hesitate to sign up for random shit anymore cuz I can just delete the email address.

I believe proton will also include it in their mail offering. I don’t buy proton mail because their free tier is more than sufficient for me. I only subscribe to the proton pass for now which is a good deal because the simplelogin stuff comes free with it. I did quite a bit of research, comparing bitwarden + simplelogin/fastmail, 1password + fastmail, etc. proton pass comes out ahead in terms of value though I’d say it’s late stage beta software more than a complete package like bitwarden or 1password. I believe it’ll have feature parity soon though.