The Web Facebook [Free Basic] is an addon that lets you request the Facebook Access Token after login.
This is thanks to the Construct Team's fast consideration and development of feature requests.
Feature Request Reference: construct3.ideas.aha.io/ideas/C3-I-624
SDK Reference: construct.net/en/make-games/manuals/addon-sdk/runtime-reference/addon-interfaces/facebook
The C3 Addon has a sample project file on how to use the addon.
The Web Facebook is mainly intended to extend the PlayFab Master Collection under the Construct Master Collection.
The full version is intended to have more features with the Construct Master Collection progresses into success.
For more information
Happy Game Development!