An infamous online debate has reignited after an optical illusion that left social media users dumbfounded.

The black and blue vs white and gold dress debate, which went viral in February 2015, caused a sensation across the globe following a post on social media. The garment appeared to be a plain bodycon number, but due to baffling lighting in an uploaded image of it, it sparked a fierce reaction with people seeing it as either blue and black or white and gold.

Internet users were split into…