Activists of civil society organizations often use social media (SM) to organize and achieve social change by sharing content across different SM technologies. These technologies themselves can be understood as non-human actors that crucially influence how activists share content and organize. This chapter focuses on how the sharing of content, which is shaped by the interplay between human and non-human actors, results in mashups, i.e., mutable interactions that emerge from disparate locales. Based on affordances theory and an ethnographic study, this chapter investigates how these mashups influence activist organizing of two civil society organizations. The study shows how the human-technology interplay that rests on the feature of “exporting” and “importing” content across SM connects various actors and interactions. The study furthermore shows the role and agency of non-human actors (algorithm-driven hashtags) in creating mashups and shows how these mashups can develop ordering and disordering effects.