Complex sentence: In March 2017 the Galaxy S8 was leaked in a video, the device had a "confidential" sticker, however, it's unknown if the device shown on the video is real or fake.
Split into simpler sentences: In March 2017 the Galaxy S8 was leaked in a video. The device shown had a "confidential" sticker, however it is unknown if the device in the video is real or fake.