Does the Marshmellow update disable youtube split screen?

[AC Question]

I upgraded from an S4 to S6 and now youtube does not work is split screen without a red subscription on the phone. It still works on my Tab S 8.4. I am running youtube version 11.22.56 and Android 5.0.2. I am hesitant to upgrade either because the large screen works great for web surfing while watching a video.