How to block Facebook webhook calls for app specific users? [duplicate] - facebook-graph-api

Question

There is documentation for test users in the Facebook Developer online documentation but how do you delete actual users where the application doesn't show in their app list anymore? This is with the knowledge of the access_token and facebook_user_id.
Used to delete Test Users:
https://graph.facebook.com/893450345999?method=delete&access_token=A2ADI1YMySweBABBGrWPNwKMlubZA5ZCrQbxwhtlEd9FIQUrOVjsGD3mnIWEbUhzDz7dkuBekMFdHvjvJ9CZAU7EMSSaZBsgN60FkMCi3AAZDZD
Running the test user link produces the following error:
"error": {
"message": "(#100) Can only call this method on valid test users for your app",
"type": "OAuthException",
"code": 100
}

Answer 1

You seek for application de-authorization:
You can de-authorize an application or revoke a specific extended permissions on behalf of a user by issuing an HTTP DELETE request to PROFILE_ID/permissions with a user access_token for that app.
permission - The permission you wish to revoke. If you don't specify a permission then this will de-authorize the application completely.
To achieve this issue request to:
https://graph.facebook.com/me/permissions?method=delete&access_token=...
Once application de-authorized it will not appear in the list of user's applications.
Update December 2021
Follow the reference for Requesting & Revoking Permissions:
To remove single permission issue a DELETE request to /{user-id}/permissions/{permission-name} passing user access token or an app access token
To de-authorize an app completely issue similar request to the /{user-id}/permissions endpoint

Answer 2

Real users 'delete' themselves from your app when they remove your app from their account, you don't have to do anything.
If you would like to know when users de-authorize your app like this, you can specify a Deauthorize Callback URL in your app's settings. As described in the docs at https://developers.facebook.com/docs/authentication/:
Upon app removal we will send an HTTP POST request containing a single parameter, signed_request, which, once decoded, will yield a JSON object containing the user_id of the user who just deauthorized your app. You will not receive an user access token in this request and all existing user access tokens that were previously issued on behalf of that user will become invalid.
UPDATE: To remove your own app from the user's authorized applications, issue an HTTP DELETE to https://graph.facebook.com/[userid]/permissions?access_token=... as per https://developers.facebook.com/docs/reference/api/user/.
Typically Graph API calls also support doing an HTTP POST with an extra parameter, method=DELETE, in case DELETE calls are not possible/supported.

Answer 3

To do it:
You must have the user access token.
Visit https://developers.facebook.com/tools/debug/accesstoken/ and debug the user access token.
Copy App-Scoped User ID
Via API call HTTP DELETE to https://graph.facebook.com/[App-Scoped User ID]/permissions?method=delete&access_token=[YOUR-APP-ACCESS-TOKEN]