Online social spaces provide much needed connection and belonging - particularly in a context of continued lack of global mobility due to the ongoing Covid-19 pandemic and climate crisis. However, the norms of online social spaces can create environments in which toxic behaviour is normalized, tolerated or even celebrated. This can occur without consequence, leaving its members vulnerable to hate, harassment, and abuse. A vast majority of adults have experienced toxicity online and the harm is even more prevalent for members of marginalized and minoritized groups, who are more often the targets of online abuse. Although there is significant work on toxicity in the SIGCHI community, approaches and knowledge have typically been siloed by the domain of investigation (e.g., social media, multiplayer games, social VR). We argue that cross-disciplinary efforts will benefit not only the various communities and situations in which abuse occurs, but that bringing together researchers from different backgrounds and specialties will provide a robust and rich understanding of how to tackle online toxicity at scale.