I am configuring my project to use Sitecore Social Connected in order to allow users to log in to the site using their Facebook account. A prerequisite of this is to have a Facebook App created (described here). Will this work when I am running the site on my machine e.g. under say localhost ? I assume I need to create a Facebook App with the "Site Url" set to localhost, but I'm not even sure if that would work and whether Facebook actually needs to be able to access my Sitecore instance? If so, I guess this could only be tested on an integration environment if it is publicly available.
Last time I created Facebook app 2 years ago and at that point I got it working with
localhost:port as Site Url and
localhost as App Domains. If that doesn't work, you could try creating a "Test App". There is a menu on the top left corner. If that also fails, this SO post has a discussion about using localhost for development of facebook apps.