The SecurityContextConstraints resource should be available on the search page. Currently, the only way to get to it is through the Explore page.
SecurityContextConstraints could be selected in the Search drop-down list and can filter the SecurityContextConstraints resources list correctly.
Verified on 4.5.0-0.nightly-2020-04-28-235851
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.