If anything occurred in Halifax, I’d say McCain and/or Tim Kaine since both were there.
McCain's always been a back stabber... it's why the press calls him a 'maverick' - means he's always available to trash a fellow Republican. And Tim Kaine? Who can forget the contempt and hatred he exhibited during the debate with Vice President Pence? He's right up there near the top of the list. Reminded me of Al Gore sighing and constantly rolling his eyes while debating Bush... disgraceful...