Facebook and linkedin not filling email field properly - python-social-auth

Question

Google and github logins are working properly but for some reason I cant get the facebook and linkedin accounts to properly fill the email fields.
Here are the involved files
__init__.py
db = SQLAlchemy(app)
login_manager=LoginManager()
login_manager.init_app(app)
# Import blueprints from app (example: from app.posts import posts)
from app.users import users
# Register all blueprints to the main app (example: app.register_blueprint(posts))
app.register_blueprint(users)
app.register_blueprint(social_auth)
#3rd part db interaction
init_social(app, db)
# Import main views from app
from app import views
#Set login bootback
login_manager.login_view ='/login'
app.context_processor(backends)
Settings.py configuration, keys have been removed from post
#Flask
SECRET_KEY = ''
SESSION_COOKIE_NAME = ''
### Python Social Auth ###
DEBUG_TB_INTERCEPT_REDIRECTS = False
SESSION_PROTECTION = 'strong'
#Redirects and Paths
SOCIAL_AUTH_LOGIN_URL = '/login'
SOCIAL_AUTH_LOGIN_REDIRECT_URL = '/'
SOCIAL_AUTH_BACKEND_ERROR_URL = '/login'
SOCIAL_AUTH_USER_MODEL = 'app.users.models.User'
SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL = True
#Facebook
SOCIAL_AUTH_FACEBOOK_KEY=''
SOCIAL_AUTH_FACEBOOK_SECRET=''
#Google
SOCIAL_AUTH_GOOGLE_KEY=''
SOCIAL_AUTH_GOOGLE_SECRET=''
#LinkedIn
SOCIAL_AUTH_LINKEDIN_KEY=''
SOCIAL_AUTH_LINKEDIN_SECRET=''
#Github
SOCIAL_AUTH_GITHUB_KEY=''
SOCIAL_AUTH_GITHUB_SECRET=''
SOCIAL_AUTH_AUTHENTICATION_BACKENDS = (
'social.backends.google.GoogleOpenId',
'social.backends.google.GoogleOAuth2',
'social.backends.google.GoogleOAuth',
'social.backends.facebook.FacebookOAuth2',
'social.backends.linkedin.LinkedinOAuth',
'social.backends.github.GithubOAuth2',
)
Here is the model itself, follows pretty closely the example provided by omab
models.py
from __future__ import absolute_import, print_function
from time import time
import functools
import uuid
import pbkdf2
from marshmallow import Serializer, fields
from app import db
ROLE_USER=0
ROLE_ADMIN=1
ROLE_GOD=2
default_img = '/assets/images/avatars/default.jpg'
class User(db.Model):
#meat n' potatoes
id = db.Column(db.Integer, primary_key=True)
img=db.Column(db.String(255), default=default_img)
username = db.Column(db.String(255))
email = db.Column(db.String(200), unique=True)
first_name = db.Column(db.String(30))
last_name = db.Column(db.String(40))
created_at = db.Column(db.BigInteger, default=time())
#controls
role = db.Column(db.SmallInteger, default=ROLE_USER)
is_active = db.Column(db.Boolean, default=True)
is_authenticated= db.Column(db.Boolean, default=True)
#password
salt = db.Column(db.String(50))
pass_hash = db.Column(db.String(255))
def __unicode__(self):
return self.email
def __repr__(self):
return '<User %r>' % self.email
def is_authenticated(self):
return self.is_authenticated
def is_anonymous(self):
return False
def is_active(self):
return self.is_active
def get_id(self):
return unicode(self.id)
def _check_password(self, password):
hash_check = pbkdf2.crypt(password, self.salt, 1000)
if hash_check ==self.pass_hash:
valid=True
else:
valid=False
return valid
def validate_user(self,password):
p=self.check_password(password=password)
if p:
return True;
else:
return False;
meta = {
'allow_inheritance': True,
'indexes': ['-created_at'],
'ordering': ['-created_at']
}
class UserSerializer(Serializer):
id=fields.Integer()
img=fields.String()
email=fields.String()
first_name=fields.String()
last_name=fields.String()

Answer 1

Found this in the docs silly of me not to realize that they would have different request parameters:
http://psa.matiasaguirre.net/docs/backends/index.html
UPDATE:
See this answer from Babken Vardanyan
https://stackoverflow.com/a/46807907/2529583