Help. Can't get back to edit security policy portlet. Is it bug?

[AP...@fidm.com]

I accidentally 'closed' the portlet using the 'close' button shown on the 
portlet title bar while I was in the edit security policy portlet, inside 
security pane from security browser as admin. (click security pane, 
security browser, then pick one security id to edit). 

1. Which portlet should I add back to the layout(I compared the layout in 
two systems and there is a 'security' portlet is missing)? How can I add 
that portlet back?  I can't edit security policy any more.  I tried to add 
portlet back the normal way but the 'add portlet' button is disabled.

2. The text shows the button is to 'close' the portlet but it actually 
delete that specific portlet from the layout at runtime.  The button shown 
as 'remove' in the customizer.  This is misleading. 

This happens on the production system.  Any help is appreciated.

Alex