Display Suite layouts not available for field collections Edit\Add forms I'm using Drupal 7 with the Display suite and Field Collection contrib modules.

For nodes entities the "Layout for..." vertical tab provided by Display Suite is available in both "Manage fields" and "Manage display". This applies also to any node content type I created, so I'm able to rearrange forms layouts used when adding\editing and when viewing nodes.

But for field collections the "Layout for ..." vertical tab is missing in "Manage fields" and it's available only in "Manage display", so I'm not able to rearrange the layout used by the add\edit form specific to field collections.

Is this a limitation of Display Suite? Any other way to rearrange the edit\add form for field collections fields?
If you are using 7.x.1, you need rel module to edit forms from other entites than node type, like field collection, user, comment, etc.
If you are using 7.x.2 you don't need that because this branch offers this feature out of the box.
For editing forms, you must go to Manage fields of your entity.

edit: just to note that rel will stop this from working on the 7.x.2 branch.