Twitter users consistently noticed when a photo with a black face and white face appears in the same post, Twitter often only shows the white face on mobile phones. The platform announced it had tested its algorithms for bias before implementing them and it did not find evidence of racial or gender bias in their testing. Images have been cropped automatically to prevent them taking up too much space on the main feed. Twitter uses several algorithmic mechanisms to focus on parts of the pictures considered more important. This is an attempt to ensure that faces and text remain visible to users using the platform through their mobile phones. Recently, a white researcher posted an image of himself close to his black colleague. Twitter's algorithm erased the part of the image with the black person. Another experiment showed that the algorithm consistently cropped the former president Barack Obama when he was in an image side-by-side with a white person. Twitter has apologised for the racist algorithm and committed to work to fix its racial bias.