This research draws on Androutsopoulos (2014) to analyse the language, language mixing phenomena and participation in online exchanges among members of a transnational community: colleagues in a project team who have been working together for over four years. Informed by sociolinguistics and Computer-mediated Discourse Analysis theory (Herring, 2004), this contribution compares the colleagues’ usual moments of sharing on WhatsApp with their interactions using the same medium during three extraordinary online moments of sharing, which are also significant off-line moments for the group. These three special moments of sharing took place after the terrorist attacks in Manchester in May 2017 and in Turku in August 2017, and the outbreak of the coronavirus (COVID-19) pandemic in Europe in March 2020. An examination of the messages exchanged during these extraordinary moments provides considerable evidence that moment, style and audience engagement are closely intertwined. While graphical elements, such as emoji, as well as textese language, are pragmatically unmarked in the typical practices of the community, their absence is the marked choice during the three special moments of sharing analysed. Importantly, the study also shows that code-switching is a key strategy to demonstrate group solidarity during moments of sharing that are special and highly significant for the participants.