(DAILYMAIL) — Your Facebook feed is probably looking a little more colourful this week.
In celebration of the Supreme Court's approval of same-sex marriage, the site is offering users a tool to overlay their profile photos with a rainbow filter.
And it's proved hugely popular. Within a few hours of the 'Celebrate Pride' tool launching, more than a million people changed their profile photos.
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But while it may seem like Facebook's intentions are noble, some people have accused the social network of carrying out another psychological test on its users.