A series to remember, plus the easteregg.
Nothing compares to this series for those warming moments, and now... for the spoiler.
When the main protagonist (the guy showing the joys of Colour) opens the curtain behind him, theres a sparkle on the tip of the large tree. I found it by I guess cheating; I held the [Tab] key through out the video until I saw a highlighted yellow square.
I repeat:
The easteregg (clickable part) is on the tip of the large tree just as "the guy on the TV screen" opens his curtains.