What's with the invalid redirect?

[Niitaayis]

[MESSAGE]
Invalid Redirect URL ([url]http://www.facepunch.com/[/url])

I have facepunch bookmarked under the url above, no /forum.php at the end
Been like this for years, and every time I login from that URL, the message pops up

When I refresh the page, it just loads up back to the main screen with me logged in like there was no problem at all

So why is [url]http://www.facepunch.com/[/url] still invalid?

[GordonTS]

garrys baby is coding the website with his mind