Facebook Reels Algorithm

Anyone know how the facebook reels algorithm works?

seems to be promoting whatever but is there anything that the algorithm favors per say?

These are not hard and fast rules but generalized preferences/observations for instance
1. Reels with trendy music, filters, and effects get an extra boost
2. Hashtags also help the algorithm
3. Vertical orientation shots and high-resolution reels
4. Reel completion rate is another factor
5. Engagement rate(reactions) or simply time spent on a content