Listing monitoring locations from the administrative WebUI is not working

If you go to Admin -> Configure OpenNMS, and then "Manage Monitoring Locations" under "Distributed Monitoring", nothing is displayed.

However, with the browser development tools open you can see the error as shown on the attached screenshot.

The underlying ReST API call works if I use curl without parameters, so it looks like the problem is passing an empty "_s" as a parameter.

Unfortunately the error on web.log is not very informative:

2019-11-04 15:34:09,485 WARN  [qtp1320263260-3198] o.o.w.r.v.AbstractDaoRestServiceWithDTO: ArrayIndexOutOfBoundsException while parsing FIQL search, ignoring: null
java.lang.ArrayIndexOutOfBoundsException: null