You can also change the view wich creates the robot options. Better then changing the core-file is to inherited it's contents in a new view and make the changes in the duplicated view. This way, the contents will be remembered after a upgrade.

here we go:

1. goto settings menu in the top (as an administrator user)

2. choose in the left panel the menu: user interface

3.  choose views

4. Then search and select for the view with the following name/contents "robots"

5.  Duplicate this view

6.  Change the name of this view immediatly to for e.q.  “myrobots”

7.  Save              <-- just to be sure                     

8.  Choose Edit 

9.   At the selection of "inhebited view” pick the original view "robots"

10. Change the content of the view with the adjustments needed.

11.   Finally save the view.

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