Looking for logging into the Webmaster Facebook site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Webmaster Facebook site. After that you can login as usual with your login credentials.
https://blogs.bing.com/webmaster/january-2018/Introducing-Social-Login-for-Bing-Webmaster-Tools
https://www.onmsft.com/news/users-of-bings-webmaster-tools-can-now-login-with-their-accounts-on-google-and-facebook
https://www.webmasterview.com/free-anonymous-web-proxy/facebook/
https://searchengineland.com/bing-webmaster-tools-adds-social-sign-feature-291655
https://www.searchenginejournal.com/bing-webmaster-tools-now-social-login-option/236569/
http://social-sponsor.com/webmaster/anleitung.html
https://developers.facebook.com/
https://developers.facebook.com/docs/sharing/webmasters/crawler/
https://www.facebook.com/webmaster/
https://developers.facebook.com/docs/sharing/
https://www.facebook.com/help/community/question/?id=10152022734959652
https://developers.facebook.com/tools/debug/sharing/
https://growthup.de/warum-ihr-die-bing-webmaster-tools-nutzen-solltet/