Only chaos

To answer your question, the joke is just overlaid atop shots of Invader Zim. The joke was never said in Invader Zim.

But here's your fun fact of the day.

The joke was never said in Red vs Blue either. Seriously. You can watch every episode and you will never find this quote because it was never said. Even the original image used (which I will post at the bottom) doesn't match up in the visual style, demonstrating that the thumbnails are from two different episodes. The source of that joke is a tumblr image that has been used since but was literally never made in Red vs Blue.