I use Tor Browser, and sometimes when I login it says that there is a potential identity leak, and I have to choose between loading content anonymously or normally.
Apparently, NoScript displays this warning when the browser sends a POST request to a third-party website.
Are you using another account like Discourse or Github to log into this site?
https://gitlab.torproject.org/tpo/applications/tor-browser/-/work_items/41112#note_2904715
No, I am not using any other service to login. Just email and password.