This article consists of an ethnographic survey conducted between 2015 and 2017 on a mailing list named échanges. Inaugurated in September 2012 by the Réseau francophone des biens communs (RFBC), this list was intended to serve as support for the constitution of a “movement of the commons”, which claimed to be “intercultural”. The authors question the effective role of the digital tool with regard to this goal of “unity in diversity”. On the one hand, they show that the digital tool has largely contributed to the deployment of a “movement of the commons” intersecting different fields. It has notably supported a wide activity of networking, exchange of information and reflection but also by allowing a large community to concretely experience this “movement”. On the other hand, they put into perspective the enthusiasm that this tool has generated. Indeed, the list does not allow the flourishing of a broad community of action and intercultural reflection. Its advent is conditioned by a set of practices that goes beyond the technical tool (openness, regulation of exchanges, etc.). Moreover, the use of a mailing list is not a neutral choice. The survey shows that it is part of a broader dynamic, characterized by the ascendancy exercised by the “digital world” (or “free culture”) on the list. In this sense, the article concludes on the need for greater reflexivity of commoners towards their own frames.