Facebook introduced a new ad option that requires advertisers to pay only when their video ad is 100% visible.
Facebook has slowly but surely tried to endear itself to advertisers, most recently with an option that only charged them if their ad was watched for at least 10 seconds. On Thursday, the social network presented a new feature, one that advertisers have long been clamoring for: the ability to pay for an ad only when it is fully visible on users' screens.