Who can see my posts?
Anyone who follows you or belongs to a group you're in can view your posts, including any attached files.
Anyone with permission to see the records, transactions, or other objects you work with can see what you post.
Actual visibility is further restricted by record‑level permissions. If someone does not have access to a specific record, they cannot see posts or files attached to that record, even if they follow you or are a member of your group.