As visual condensations of protest movements symbols reference their key messages. By spreading a symbol, movements enhance their visibility and potential impact. Thus, activists have an interest in the popularization of symbols, understood as widespread recognition and usage beyond the movement constituency. However, processes of popularization also entail shifts in meaning that alter the original movement message. The article traces back how the smiling sun and the rainbow flag became popular. It analyzes the features of the symbols as well as underlying conditions and relevant actors to understand trajectories of popularization.