Inter-platform ecosystems in Europe for the year 2020. Source: Carballa-Smichowski and others (2021). The thickness of the links is proportional to the share of total received referral traffic. Traffic below 10 per cent of total received referral traffic, between platforms belonging to the same conglomerate and including non-platform domains excluded. Twenty European countries were included. The platforms in the same painted area are within the boundaries of the same ecosystem.