That depends on which English-speaking country you live in. The spelling of "color" predates the founding of the United States by a few centuries. Colonial America maintained some older English spellings while BrE has been influenced by French spellings. Another example: theater (AmE), theatre (BrE) = théâtre (Fr)
Edit: I have had no problems with pop ups on this link. Perhaps the problem is with your server.
Unrelated to the spelling of color/colour, the link you provided had quite a few pop-up ads, as well as a lot of junk--I'm not sure if that is because less ability to control from a phone? Good info, but slick ads 'jumping' under the finger, waiting for a miss-stroke.
Aside from this my phone behaves normally.