"You canker blossom!" 3 Shakespearean Insults
"to talk, to chatter," slang, 1950, probably echoic (cf. Australian slang yacker "talk, conversation," 1882). Yackety is recorded from 1953.
And so on; so they say repeatedly: Snyder is too old, too abrasive, yadda yadda, on and on (1990s+)