Presumably you aren’t actually trying to connect to this site ?
If yes, your first action, clear your browser cache and cookies (and restart your browser).
If this resolved it, you may visited a site with cross site 3rd party cookies/scripting.
If no change, try running the browser with add-ons/extensions disabled.
If this resolves it check what add-ons/extensions you have recently added and or updated.
Just keep monitoring and if it appears again, first try the disabling add-ons/extensions as it could be one of those causing the browser cache and cookies issue when it reaches out to a site.