Facebook Pre-rolls on the roadmap
Facebook has on the roadmap to start testing video ads before the content starts. Until now facebook only had mid-rolls video ads, but with this test, facebook is including pre-roll video ads on their inventory.

In July, Zuckerberg said no to pre-roll because facebook "model is not one where you come to Facebook to watch one piece of content, you come to look at a feed." This is a change in this vision, confirmed by Ad Age with advertisers who are familiar with the social network's strategy.
The pre-rolls ads on facebook should be available initially on the new tab Watch, where users can find a feed of videos:
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