  Personal moderation tools on social media platforms let users control their
news feeds by configuring acceptable toxicity thresholds for their feed content
or muting inappropriate accounts. This research examines how four critical
psychosocial factors - fear of missing out (FoMO), social media addiction,
subjective norms, and trust in moderation systems - shape Facebook users'
configuration of these tools. Findings from a nationally representative sample
of 1,061 participants show that FoMO and social media addiction make Facebook
users more vulnerable to content-based harms by reducing their likelihood of
adopting personal moderation tools to hide inappropriate posts. In contrast,
descriptive and injunctive norms positively influence the use of these tools.
Further, trust in Facebook's moderation systems also significantly affects
users' engagement with personal moderation. This analysis highlights
qualitatively different pathways through which FoMO and social media addiction
make affected users disproportionately unsafe and offers design and policy
solutions to address this challenge.
