This is a regression from 4.16 as I was not able to repro this issue in //UE4/Release-4.16 at CL 3514769.
and double click to open it
There are no constraint axes visible in the viewport. Pressing the Constraint button does not change this.
Constraint axes are visible.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-47035 in the post.