Terrorists and violent extremists are manipulators seeking to exploit stress factors in our societies. The Covid-19 pandemic, its ensuing lockdown measures, as well as the spread of related mis- and disinformation online, thus represented an almost ideal opportunity for malevolent actors to exploit. Far-right violent extremists, in particular, quickly jumped on the opportunity offered by the Covid-19 crisis to anchor their hateful ideas into the mainstream and recruit new members. Whilst manifesting itself mostly online, this exploitation was not limited to the online sphere. It materialised in real world events as violent extremists blended themselves into anti-lockdown protests and as terrorists’ plans were eventually thwarted. Whilst the tech sector promptly responded to the wave of mis- and disinformation, the rapid changes in content moderation policy bear important consequences for the future of content moderation and freedom of expression online. Indeed, the global tech sector, especially social media and content-hosting platforms, was particularly quick to respond to the spread of Covid-19 disinformation and conspiracy theories. In this insight piece, Tech Against Terrorism analyses how far-right violent extremists exploited the instability caused by the Covid-19 pandemic and what the tech sector’s response means for online freedom of expression and platforms’ accountability.