On my Stage, I have a YouTube video. I also have some elements that I'd like to have appear/disappear at certain points when the video is playing.
For instance, while the video is playing, the Stage is empty (except for the video). Then, when the video gets to 5 seconds, a photograph appears below the video. Then at 12 seconds, another photo appears.
This would need to be controlled by the time of the video, since the viewer may pause it, then restart it, and things would get out of sync otherwise.