This is a new Facebook feature called "add groups", that replaced their "share groups" feature.

It's not as obvious, so here's how to use it:

• Must be on the MOBILE Facebook App
• Go into a Group that you are a member of
• Click the box to start typing a post [note: do NOT create your post, start typing, or add a photo first, the option disappears]
• at the top of the white box you'll see "add groups" click on it (see screenshots)
• a drop down menu will appear and state you can select up to 50 groups to share this post to
• select all the groups you want to share to
• close the menu, create your post, and hit "post"

If you're looking for more amazing groups that are promo friendly, grab out PROMO DAYS guide here with our favorite groups!