Social Login for vBulletin 4/5 allows your users to login and register with 35+ social networks. It increases your vBulletin user registration rate by simplifying the registration process for new users and provides permission-based social data retrieved from the social network profiles.
The documentation link in the github repo description is wrong.
In the description:
http://docs.oneall.loc/plugins/guide/social-login-vbulletin/
The correct one in the readme:
https://docs.oneall.com/plugins/guide/social-login-vbulletin/
(.com vs .loc)