http://te-in.facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion/business/help/675615482516035
For example, if an ad is on screen and someone scrolls down, and then scrolls back up to the same ad, that counts as 1 impression. If an ad is on screen for someone 2 different times in a day, that counts as 2 impressions. This method of counting video impressions differs from industry standards for video ads. With the exception of ads on Meta Audience Network, impressions are counted the same way for ads that contain either images or video.