After publish a post , it state something like the following.
failed-again

“Failed posting to your Facebook timeline.
Error:{“message”:”(#100)You haven’t enabled Explicitly Shared for this action type ( ACTION_CODE_NO_HERE ) yet.”

Fixing it , is by going to app Open Graph. click on Action Type.
Find the desired Action Code by mouse-over and see the matching code number.

Click advance. then at “Capabilities”.
Tick. the bottom most “Explicitly Shared – Publish a story ..”

publish

References :

https://developers.facebook.com/docs/sharing/best-practices#permissions