When co-witnesses exchange information, false information may be presented, and false memories could be created. This co-witness suggestibility effect has been studied in face-to-face interactions, and little is known about the impact of online discussions on co-witnesses' memories. In two experiments, we explored whether: (1) the co-witness suggestibility effect appeared following online discussion; and (2) enlightenment instructions reduced the effect. We created a virtual variant of the MORI procedure, the MORI-v technique, in which participants watched a short film of a crime on a smartphone and then discussed the event via an instant-messaging app. Results replicated the classic co-witness suggestibility effect: false information presented by witnesses was often incorporated in their memories. Also, enlightenment instructions reduced the co-witness suggestibility effect, just as in the misinformation paradigm. This research showed that online-based communication might induce memory distortions and that cognitive science may help to find ways to protect us from them.