vBulletin (a forum package like phpBB, but not open source and you had to pay for it) had a shadowban feature they called "Tachy Goes to Coventry" and there are

vBulletin (a forum package like phpBB, but not open source and you had to pay for it) had a shadowban feature they called "Tachy Goes to Coventry" and there are references to it as far back as 2003. https://forum.vbulletin.com/forum/general/chit-chat/75468-tachy-goes-to-coventry https://forum.vbulletin.com/forum/general/chit-chat/75468-ta...