https://phys.org/news/2018-11-social-media-labor-discrimination.html

A significant 41.7% gap between the two applicants' callback rates highlighted that personal online profiles are used by recruiters as a source of information to discriminate against applicants of foreign origin.

During the experiment, the Facebook default layout changed as Facebook introduced sub-tabs within profiles. This change reduced the salience of the information related to the applicants' language spoken. After the layout change, the difference in callback rates faded away. This suggests that the screening conducted by the employers does not go beyond the main pages of profiles. It also indicates that design choices made by online platforms, such as which information is displayed and how it is displayed, may have important consequences on the extent of discrimination.