The old 2015.3 release is terrible outdated and full of bugs. Because of this all serious OpenSCAD users are using development snapshots.
In the ideal case, the OpenSCAD team would release a current snapshot as a new release, but even though I have requested this a couple of years, they have not had time to do it. With the current situation the best solution would be to create a cad/openscad-current port.
A commit references this bug:
Date: Sun Apr 22 18:14:41 UTC 2018
New revision: 468045
Add openscad-devel as of 2018.04.19
Since mr pushed cad/openscad-devel this ticket should be closed. Thought?