2016-01-13 UTC
# 
petermolnar !tell singpolyma pingbacks _were_ are widely supported. Nowadays they are widely ignored or considered spam. It'd need additional magic to support types - like, fav, reply, repost, etc -, and by a short research, none blogger or blogspot supports it (any more?). The support you're referring to is long gone, maybe except for WordPress where it's ignored.