To comment anonymously in Facebook groups, the group must allow anonymous posts. You can only comment anonymously on your own posts. Just find your anonymous post, click “comment,” and it will stay ...
If you'd like to post something in a Facebook group without revealing your name, use Facebook's anonymous posting feature. It's easy to do, assuming that a group administrator has enabled the feature.
If you're in a Facebook group and you get that urge to share an opinion but would prefer not to have your name attached to it, you can do so. Facebook's "Anonymous Post" feature was first introduced ...