Bootlegging behavior enables employees to better utilize their creativity to contribute more to their organization. Therefore, the facilitative antecedents of employee bootlegging must be emphasized. The role of family supportive supervisor behavior (FSSB), which is critical in the increasingly prevalent telecommuting context of the post-pandemic era, in facilitating employee bootlegging behavior has not received enough attention. Thus, combining the telecommuting context with the work–home resource model and using thriving at work and proactive personality as a mediator and moderator, respectively, we constructed a moderated mediation model to test whether, how, and when FSSB facilitates employee bootlegging behavior. The empirical results, based on an analysis of 277 telecommuters, indicate that FSSB positively influences employee bootlegging behavior directly and indirectly through thriving at work, and proactive personality plays a moderated mediating role in the first stage. This study expands research on the antecedents of employee bootlegging behavior, deepens understanding of FSSB and thriving at work in the telecommuting context, and provides suggestions on addressing the challenges of innovation for telecommuters.