Symantec Clicktime Protection is no longer scanning the link you have opened. The site you are trying to visit may be harmful. If you know the site is safe, you can proceed by copying the following URL and pasting it into your browser:

https://github.com/notifications/unsubscribe-auth/ASMEXYI6WXYX5RVRJKVWNQ3T4VQUXANCNFSM5CCLYHQA

Learn more about Advanced Threat Protection and how Symantec can help you.