Netflix trials personalised pre-roll video ‘previews’ to promote its original programming

Netflix has been testing the use of pre-roll video ads - what it calls ‘previews’ -  that are personalised to each viewer’s interests and used as a way to promote the streaming services' big-budget original programming.
The ‘previews’, which are 30-seconds in length, act as a trailer for upcoming Netflix original series or movies to give viewers a better idea about what the show is about rather than using a still image.
These 30-second spots play before the sho