Netflix is adding a "mystery box" feature for kids profiles on TVs, with the aim of surfacing new titles to young viewers -- an audience prone to repeat-watching the same programs over and over. 

The feature adds a sparkly rectangle in the middle of the "Favorites Row" at the top of the homepage on a kids profile. Hovering over the "mystery box" will reveal a new title, Netflix said. 

Netflix, the world's dominant subscription streaming service with 221 million members, has been investing to amp up its appeal for its youngest viewers in recent years. The lastest move comes at a time when streaming video has never been more popular -- and the competition around it never more fierce. In the last two years, media giants and tech heavyweights have launched their own rivals to Netflix, with services like Apple TV Plus, Disney Plus, HBO Max and Peacock rolling out. 

These so-called streaming wars also affect how many services you must use -- and pay for -- to watch your favorite shows and movies online.