Long-time LastPass Premium user here, and I love LastPass. I'd imagine that I've sent at least 100 people to become users over my career because I always suggest it to friends and co-workers. Anyway, I have a feature suggestion, so I apologize if this is the wrong place to post it.
One thing that we all encounter are times where you are joining or signing up for something online, but you don't need a password saved for a new account because you choose an authentication signup like "Sign Up with Google", or "Sign Up with Github". Well personally, I tend to use those options often but sometimes just can't remember IF I've used it in the past for an account, and if so, WHICH of them I might have used. So I'm left wondering "Wait, haven't I signed up for this before?".
So often times, what I do is I try to remember to STILL "Add" a password for that site for LastPass and for the username, I'll write "USE GITHUB" or "USE GOOGLE" as a reminder to me that I've signed up before and what I used to signup.
But it would be really useful if this was an actual LastPass feature, where the automatic "Save this Password" popup still occurred in these situations, but instead of it saving a normal "username and password", instead maybe LastPass could add a new password "type" for authentication where you can simply select "Github" or "Goolge" or "Amazon" or "Apple" or whatever you used to signup, and then maybe even also add your "account" so for example, it'd be "Goolge" and for account "MyMainAccount@gmail.com" because a lot of us have multiple Google accounts, Github accounts, etc.
Anyway, just my 2 cents for a suggestion! Thanks for reading! 
