I noticed that if I went to Custom Search from any of the other child searches (Docker, Maven, NuGet, Raw) I got a continual loading mask that did not go away.
If you go from Search parent or outside stuff (such as Welcome or Browse) it works.
This occurs with Debug on and off and nothing in the log/js console shows (though I mull if it's really continual that's why).
This occurs with contents in the repos or with a fresh (content free) install.
None of the other child searches seem affected in this way.
I've attached a screen since it's about the same info as a vid, but if you want a vid let me know.
I did not check older NX3 or NX2 at this time.