With its content from other networks and originals like “Orange Is The New Black” and “Daredevil,” Netflix’s catalog is getting increasingly larger. But for some users, Netflix is trying a notable way to tell users about its shows.

Netflix is testing out preroll ads on a limited number of users to highlight upcoming or current Netflix shows or movies based on a user's past viewing history, Cord Cutter News reported. The ads, which are skippable and 30 seconds long, have been seen on Netflix platforms, including its web client, consoles and Roku devices. In a statement to TechCrunch, Netflix confirmed it was doing some limited testing with preroll ads.

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This current test is not the first time Netflix has experimented with how it advertises its own shows. Netflix briefly tested in 2015 post-roll ads at the end of shows that highlighted other Netflix original content. In a statement on Facebook at the time, Netflix CEO Reed Hastings shot down the idea that general advertising from third parties would come to Netflix and said the company was “just adding relevant cool trailers for other Netflix content you are likely to love.”

For Netflix, figuring out a way to promote its own content without alienating users remains a work in progress. One way Netflix has tried to do so is the newer video preview for shows or movies on its dashboard. When you move the browser selector over a show in Netflix’s homepage, a short trailer plays that gives a brief preview of the program. Similar preroll ads are done by companies like Amazon, along with other premium cable channels like Showtime and HBO. As TechCrunch notes, this feature led to Netflix’s current preroll ad testing because the company found the previews improved viewer watching rates.

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But at the same time, users — especially on a subscription service like a Netflix — are generally resistant to the kind of advertising traditionally associated with TV or YouTube.

Netflix’s advertising qualifier that limits ads to Netflix’s own content is an important note here. Users will generally be open to seeing trailers for programs they could be interested in, and considering how Netflix’s own originals catalog now encompasses everything from Broadway plays like “Oh, Hello” to overseas programming, users are increasingly unlikely to find everything they could be interested in watching.

But if Netflix started taking advertising from outside sources, there’d likely be a significant backlash against the streaming company. For users who want to opt out of testing entirely, you can do so by going through your account settings and disabling Test Participation.