https://techcrunch.com/2020/10/01/facebook-election-ad-ban-delegitimize-election-results/

Following a particularly dark and vivid display of the threats to the 2020 U.S. election during Tuesday’s first presidential debate, Facebook has further clarified its new rules around election-related ads.

Facebook is now expanding its political advertising rules to disallow any ads that “[seek] to delegitimize the outcome of an election” including “calling a method of voting inherently fraudulent or corrupt, or using isolated incidents of voter fraud to delegitimize the result of an election.”