Configure ldap config to a valid server with 5000 users.
Open users management.
Change the source to LDAP.
Nexus now makes 5000+ group member queries and tries to load 5000 records into the Nexus UI. More than likely Nexus UI will timeout and not render anything - meanwhile the queries are happily proceeding as requested in the backend.
This will either crash LDAP, crash Nexus or crash the browser.