Facebook recently added a few changes to video metrics. One of them is the clicks-to-play video views or 'Video Plays' metric.
This is important because advertisers can now bring their FB Insights and Ad Manager engagement rate formulas closer. This is something I have shared earlier on this blog, on why there's a difference in engagement rate between Facebook Insights and Facebook Ad Manager.
In my current ad account, it says 'metric in development' for 'Video Plays'. As per below announcement, this would be rolling out in the coming weeks.
At the moment, 'Unique clicks to play video' is a metric that shows up in Facebook Ads API but I can't seem to get it to populate [in DataStudio]. Tried it with month as a dimension the first time and later with Post Message. Didn't work. Perhaps, this will change quickly.