Enable edit of user role membership option from Administration missing on 25B

Summary:

Enable edit of user role membership option from Administration missing on 25B.

We want to Hide Add user from edit role tab and Page composer customization is not allowed on these pages. and the check box Enable edit of user role membership option from Administration missing

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Where as in the documents i referred it says there should be a check box

How to hide the Add user from with in role edit screen?