Google+Facebook add-ons developed by Crossrider’s is Firefox, chrome and internet explorer based extension which is main wary for Google+ and Facebook. So it is susceptible to vulnerabilities.
It allows the Google+ users to stream the Facebook within the Google+ interface, which is good for for users who want single platform to check everything. But by checking the coding of this extension, security firms advises that it could be serious security risk to users and they does not recommend use of this extension.
Another main reason for suspecting this adds-on is that it is created with in 24 hours after the creation of Google+ as well as there is major security risk in downloading external java script file during installation.
It is reported that it behaves like Malware like changing search preferences and email signatures.
So it is extremely recoomenndation to not use this extension and other extension if they’ve been created quickly and without due concern for security.