That's funny. It didn't for years up to at least a month ago or so and also doesn't seem to on mobile now for me, but I didn't check it on desktop before posting the comment!

Edit: it was hidden Aug 16th[1] but previously hiding it has been reverted[2][3][4] for at least 2 years per WP:DISC[5]

[1]: https://en.wikipedia.org/w/index.php?title=McCollough_effect... [2]: https://en.wikipedia.org/w/index.php?title=McCollough_effect... [3]: https://en.wikipedia.org/w/index.php?title=McCollough_effect... [4]: https://en.wikipedia.org/w/index.php?title=McCollough_effect... [5]: https://en.wikipedia.org/wiki/Wikipedia:Content_disclaimer