I recently started receiving deprecation warnings in Chrome when using in lined url authentication like https://user:firstname.lastname@example.org. Chrome 59 is ear marked to remove this authentication method. see this chrome issue
what are all of the other authentication methods available for use with the CBL Rest API?
Are you talking about requests made from JS to the in-app REST API itself? Use HTTP Basic auth, i.e. add an Authorization header to your requests.