Prerequisite
Have applied patch in this issue to fix the initial issue of quickedit not working with inline entity form - complex.
Problem
When using quickedit to edit any multi-value field that is using inline entity form - complex, changing order of items by drag and drop or removing item would not trigger "save" button so there is no way to save the change
Steps to reproduce
1. Install Inline Entity Form module.
2. Create a content type
3. Create Entity Reference field(unlimited value) to reference any content type
4. Manage form display and change widget to Inline entity form - Complex
5. Create test node and add at least two values in the Entity Reference field
6. Go to test node, click quickedit, then edit the Entity Reference field (if there is network problem, apply patch in prerequisite)
7. Try to remove one value in the field, and there is no option to save. Click X will close quickedit without saving.
8. Try to change order of the values in the field by drag and drop, and there is no option to save. Click X will close quickedit without saving.
Expected behavior
When removing items in fields (inline entity form - complex) or dragging items to change order in quickedit, "save" button should be triggered by those two events
What happened instead
No option to save when removing items in fields (inline entity form - complex) or dragging items to change order in quickedit
See video recording:
https://www.drupal.org/files/issues/2019-04-15/quickedit%20save%20not%20...
https://www.drupal.org/files/issues/2019-04-15/tabledrag%20can%20not%20b...