X is making a significant change to its crowd-soruced fact checking tool in an attempt to stem the flow of misinformation on its platform. The new rule is one that will be familiar to professional fact checkers, academics and Wikipedia editors, but is nonetheless new to X's approach to fact-checking: the company will now require its volunteer contributors to include sources on every community note they write. The company announced the change in a post on X, shortly after Wired reported that some community notes contributors are worried the tool is being manipulated by bad actors and worse...