Since version 1.7, it is no longer possible to copy and paste configuration tabs in Workbench. This makes working with prefabs inherited from _base quite tedious. In previous versions, you could easily copy a tab from an existing, working prefab and paste it into your new one to edit only what was needed.
Steps to Reproduce:
Open Workbench and create, inherit, or duplicate a prefab.
Open a similar reference prefab side-by-side.
Open a shared component in the reference prefab and copy a tab (as shown in the image below).
Try to paste it into your new prefab (the "Paste" option is unavailable/disabled).