Google had implemented OpenID Discovery Spec at https://accounts.google.com/.well-known/openid-configuration which allows developers and users to find the necessary URLs and keys for OpenID authentication.
I was wondering what the Facebook and possibly other (e.g. Microsoft Live) equivalents are so I can use Facebook and others in a standard fashion.
SalesForce also has a discovery URL https://login.salesforce.com/.well-known/openid-configuration
Facebook's login mechanism/protocol is not based on OpenID Connect. Facebook uses a proprietary extension of OAuth 2.0 but it is not the standardized one that OpenID Connect specifies. Hence there's no point in expecting Facebook to publish OpenID Connect Discovery documents, unlike Google and Salesforce that do adhere to the standard.
Here is the OpenID Connect Discovery URL for Microsoft Azure AD:
https://login.windows.net/common/.well-known/openid-configuration
