Some groups in Facebook have the “seen by” feature for all post—mine doesn’t.
How can I add this feature to my group? Is this related to number of members or admins?
Facebook Community Forum already has the answer: If your group is less than 250 members, "seen by" feature is automatically activated (you will not able to find it in group setting). Once your group members exceed 250, this feature will be disabled.
Thank you for your interest in this question.
Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.
Would you like to answer one of these unanswered questions instead?