How to add LinkedIn login and registration to WordPress

Login with your LinkedIn account at the following page https://www.linkedin.com/developer/apps then click the "Create app" button.

Fill all the required fields of the form and as "website url" enter the url of your website. 

Now that your app has been created, navigate to the "auth" tab and scroll down to the "Redirect urls" section. Enter your webiste url followed by ?pno_social=1&provider=linkedin.

From that same page, make a copy of the Client ID and Client Secret keys. Now login into your WordPress dashboard and navigate to "Settings → Posterno → Account → Social login" and locate the settings LinkedIn Client ID and LinkedIn Client Secret and type the keys from your LinkedIn APP.